SACM C. Coffin
Internet-Draft B. Cheikes
Intended status: Informational C. Schmidt
Expires: July 25, 2016 D. Haynes
The MITRE Corporation
J. Fitzgerald-McKay
Department of Defense
D. Waltermire
National Institute of Standards and Technology
January 22, 2016
SACM Vulnerability Assessment Scenario
draft-coffin-sacm-vuln-scenario-01
Abstract
This document provides a core narrative that walks through an
automated enterprise vulnerability assessment scenario. It is
aligned with the SACM use cases and begins with an enterprise
ingesting vulnerability description data, followed by identifying
endpoints on the network and collecting and storing information about
them to enable posture assessment, and finally ends with assessing
these endpoints against the vulnerability description data to
determine which ones are affected. Processes that specifically
overlap between this scenario and SACM use cases will be noted where
applicable. Specifically, the relationship between this document and
the SACM use case building block capabilities and the usage scenarios
will be covered.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on July 25, 2016.
Coffin, et al. Expires July 25, 2016 [Page 1]
Internet-Draft SACM Vuln Scenario January 2016
Copyright Notice
Copyright (c) 2016 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Assumptions . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Endpoint Identification and Initial (Pre-Assessment) Data
Collection . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.1. Identification . . . . . . . . . . . . . . . . . . . . . 6
3.1.1. SACM Use Case Alignment . . . . . . . . . . . . . . . 6
3.2. Processing Artifacts . . . . . . . . . . . . . . . . . . 6
3.3. Endpoint Data Collection . . . . . . . . . . . . . . . . 7
3.3.1. SACM Use Case Alignment . . . . . . . . . . . . . . . 8
3.4. Implementation Examples . . . . . . . . . . . . . . . . . 9
4. Vulnerability Description Data . . . . . . . . . . . . . . . 9
4.1. SACM Use Case Alignment . . . . . . . . . . . . . . . . . 10
4.2. Implementation Examples . . . . . . . . . . . . . . . . . 10
5. Endpoint Applicability and Assessment . . . . . . . . . . . . 10
5.1. Applicability . . . . . . . . . . . . . . . . . . . . . . 11
5.1.1. SACM Use Case Alignment . . . . . . . . . . . . . . . 11
5.2. Secondary Assessment . . . . . . . . . . . . . . . . . . 11
5.2.1. SACM Use Case Alignment . . . . . . . . . . . . . . . 12
5.3. Implementation Examples . . . . . . . . . . . . . . . . . 13
6. Assessment Results . . . . . . . . . . . . . . . . . . . . . 13
6.1. SACM Use Case Alignment . . . . . . . . . . . . . . . . . 14
6.2. Implementation Examples . . . . . . . . . . . . . . . . . 15
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
8. Security Considerations . . . . . . . . . . . . . . . . . . . 15
9. Informative References . . . . . . . . . . . . . . . . . . . 15
Appendix A. Change Log . . . . . . . . . . . . . . . . . . . . . 16
A.1. Changes in Revision 01 . . . . . . . . . . . . . . . . . 16
Appendix B. Continuous Vulnerability Assessment . . . . . . . . 17
Appendix C. Priority . . . . . . . . . . . . . . . . . . . . . . 18
Appendix D. Data Attribute Table and Definitions . . . . . . . . 19
D.1. Table . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Coffin, et al. Expires July 25, 2016 [Page 2]
Internet-Draft SACM Vuln Scenario January 2016
D.2. Definitions . . . . . . . . . . . . . . . . . . . . . . . 22
Appendix E. Alignment with Other Existing Works . . . . . . . . 24
E.1. Critical Security Controls . . . . . . . . . . . . . . . 24
E.1.1. Continuous Vulnerability Assessment . . . . . . . . . 24
E.1.2. Hardware and Software Inventories . . . . . . . . . . 26
Appendix F. SACM Usage Scenarios . . . . . . . . . . . . . . . . 26
Appendix G. SACM Requirements and Charter - Future Work . . . . 28
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 28
1. Scope
The purpose of this document is to describe a detailed scenario for
vulnerability assessment, and identify aspects of this scenario that
could be used in the development of an information model. This
includes classes of data, major roles, and a high-level description
of role interactions. Additionally, this scenario intends to inform
engineering work on protocol and data model development. The focus
of the document is entirely intra-organizational and covers
enterprise handling of vulnerability description data. The document
does not attempt to cover the security disclosure itself and any
prior activities of the security researcher or discloser, nor does it
attempt to cover the specific activities of the vendor whose software
is the focus of the vulnerability description data (i.e., the
vulnerable software).
For the purposes of this document, the term "vulnerability
description data" is intended to mean: "Data intended to alert
enterprise IT resources to the existence of a flaw or flaws in
software, hardware, and/or firmware, which could potentially have an
impact on enterprise functionality and/or security." For the purpose
of this scenario, such data also includes information that can be
used to determine (to some level of accuracy, although possibly not
conclusively) whether or not the flaw is present within an
enterprise, when compared to information about the state of the
enterprise's endpoints. For those who are familiar with current
security practices and terminology, the use of vulnerability
description data is also synonymnous with security bulletin or
advisory.
This document makes no attempt to provide a definition of a
normalized data format (e.g. industry standard) for vulnerability
description data although there is nothing precluding the development
of such a normalized data format. Also, it does not attempt to
define procedures by which a vulnerability discoverer coordinates the
release of vulnerability description data to other parties.
Coffin, et al. Expires July 25, 2016 [Page 3]
Internet-Draft SACM Vuln Scenario January 2016
2. Assumptions
A number of assumptions must be stated in order to further clarify
the position and scope of this document.
o The document begins with the assumption that the enterprise has
received vulnerability description data, and that the data has
already been processed into a format that the enterprise's
security software tools can understand and use. In particular,
this document:
* Does not discuss how the enterprise identifies potentially
relevant vulnerability description data.
* Does not discuss how the enterprise collects the vulnerability
description data.
* Does not discuss how the enterprise assesses the authenticity
of the vulnerability description data.
* Does not discuss parsing of the vulnerability description data
into a usable format.
o The document assumes that the enterprise has a means of
identifying enterprise endpoints. This could mean identifying
endpoints as they join the network, actively scanning for
connected endpoints, passive scanning of network traffic to
identify connected endpoints, or some other method of accounting
for the presence of all endpoints in the enterprise. The document
also does not distinguish between physical endpoints and
virtualized endpoints.
o The document assumes that the enterprise has a means of extracting
relevant information about enterprise endpoints. Moreover, this
extracted information is expressed in a format that is compatible
with the information extracted from the vulnerability description
data. The document:
* Does not specify how relevant information is identified.
* Does not specify the mechanics of how relevant information is
extracted from the data sources (such as the endpoint itself).
* Does not specify how extracted endpoint information and
vulnerability description data is normalized to be compatible.
Note that having a means of extracting relevant information about
enterprise endpoints is within the scope of the SACM Endpoint
Coffin, et al. Expires July 25, 2016 [Page 4]
Internet-Draft SACM Vuln Scenario January 2016
Security Posture Assessment process. In the case of this
document, this sub-process is assumed to be existent.
o The document assumes that all information described in the steps
below is available in the vulnerability description data and
serves as the basis of this assessment. Likewise, the document
assumes that the enterprise can provide all relevant information
about any endpoint needed to perform the described analysis. The
authors recognize that this will not always be the case, but these
assumptions are taken in order to show the breadth of data
utilization in this scenario. Less complete information may
require variations to the described steps.
o The document assumes that the enterprise has a policy by which
assessment of endpoints based on vulnerability description data is
prioritized. The document:
* Does not specify how prioritization occurs.
* Does not specify how prioritization impacts assessment
behaviors.
o The document assumes that the enterprise has a mechanism for long-
term storage of vulnerability description data and endpoint
assessment results (e.g., a data repository).
o This document assumes that the enterprise has a procedure for
reassessment of endpoints at some point after initial assessment.
The document:
* Does not specify how a reassessment would impact individual
assessment behaviors. (i.e., it is agnostic as to whether the
assessment procedure is the same regardless of whether this is
the first or a subsequent assessment for some set of
vulnerability description data.)
* Does not provide recommendations or specifics on reassessment
intervals.
3. Endpoint Identification and Initial (Pre-Assessment) Data Collection
The first step in this scenario involves identifying endpoints and
collecting the basic or minumum set of system information attributes
from them such as operating system type and version. Further
examples of system information and attributes can be found below in
the section titled Endpoint Data Collection. This identification
occurs prior to the receipt of any specific vulnerability description
data and is part of the regular, ongoing monitoring of endpoints
Coffin, et al. Expires July 25, 2016 [Page 5]
Internet-Draft SACM Vuln Scenario January 2016
within an enterprise. This process is not meant to report on, or
gather data for any specific vulnerabilities. The information
gathered during this step could be applied in many enterprise
automation efforts. Specifically, in addition to vulnerability
management, it could be used by configuration and license management
tasks. All of the information collected during this step is stored
in a central location such as a Repository.
This activity involves the following sub-steps:
3.1. Identification
Prior to any other steps, the identification of endpoints must occur.
This involves locating (at least virtually) and distinguishing
between endpoints on the network in a way that allows each endpoint
to be recognized in future interactions and selected for specific
treatment. This not only allows later steps to determine the scope
of what endpoints need to be assessed, but also allows for the unique
identification of each endpoint. Unique and persistent endpoint IDs
are used to allow for endpoints to be tracked over time and between
sensors as well as allow for proper counts of assets during
inventories and other similar collections. Endpoint identity can be
established by collecting certain attributes that allow for unique
and persistent tracking of endpoints on the enterprise network.
Examples include, but are not limited to, IP address, MAC address,
FQDNs, pre-provisioned identifiers such as GUIDs or copies of serial
numbers, certificates, hardware identity values, or similar
attributes. It is important to note that the persistency of these
attributes will likely vary depending on the enterprise. For
example, a statically assigned IP address is much more persistent
than an IP address assigned via DHCP.
3.1.1. SACM Use Case Alignment
This sub-step aligns with the Endpoint Discovery, Endpoint
Characterization, and Endpoint Target Identification building block
capabilities. The alignment is due to the fact that the purpose of
this sub-step is to discover, identify, and characterize all
endpoints on an enterprise network.
3.2. Processing Artifacts
Processing artifacts, such as the date and time the collection was
performed, should be collected and stored. This timestamp is
extremely important when performing later assessments, as it is
needed for data freshness computations. The organization may develop
rules for stale data and when a new data collection is required.
This metadata is also helpful in correlating information across
Coffin, et al. Expires July 25, 2016 [Page 6]
Internet-Draft SACM Vuln Scenario January 2016
multiple data collections. This includes correlating both pre-
assessment data and secondary assessment data (sections 4.3 Endpoint
Data Collection and 6.2 Secondary Assessment).
3.3. Endpoint Data Collection
The enterprise should perform ongoing collection of basic endpoint
information such as operating system and version information, and an
installed software inventory. This information is collected for
general system monitoring as well as its potential use in activities
such as vulnerability assessment.
Some examples of basic information to collect about endpoints in this
pre-assessment process could include:
o Endpoint type - traditional (e.g., workstation, server, etc.)
network infrastructure (e.g., switches, routers, etc.), mobile
(e.g., cell phones, tablets, laptops, etc.), and constrained
(e.g., industrial control systems, Internet of Things, etc.)
o Hardware version/firmware - e.g., BIOS version, firmware revision,
etc.
o Operating system - e.g., Windows, Linux, Mac OS, Android
o Operating system attributes - e.g., version, patch level, service
pack level, internationalized or localized version, etc.
o Installed software inventory - Would include the software names
and versions and possibly other high-level attributes. Could be
used to quickly determine endpoint applicability when new
vulnerability description data arrives.
Some additional and more advanced information to collect from
endpoints in this pre-assessment process could include:
o Open ports and enabled services - This would include applications
listening for incoming connections on open ports as well as
services that are starting, running, suspended, or enabled to run
pending some event.
o Operating system optional component inventory - some OS' have
optional components that can be installed which may not show up as
separate pieces of software (e.g., web and ftp servers, demo web
pages, shared libraries, etc.). Note that this could also occur
within third-party applications as well.
Coffin, et al. Expires July 25, 2016 [Page 7]
Internet-Draft SACM Vuln Scenario January 2016
o Endpoint location - physical location (e.g., department, room,
Global Positioning System (GPS), etc.), logical location (e.g.,
what network infrastructure endpoints (e.g. switches, wireless
access point, etc.) an endpoint is connected to, etc.
o Purpose - describes how the endpoint is used within the enterprise
(e.g., end-user system, database server, public web server, etc.)
o Criticality - enterprise defined rating (possibly a score) that
helps determine the criticality of the endpoint. If this endpoint
is attacked or lost, what is the impact to the overall enterprise?
It is important to note that some of these attributes may exist
natively on the endpoint whereas other attributes may be assigned by
a human, computed, or derived from other data and may or may not be
available for collection on the endpoint.
Furthermore, the possibility should be left open for enterprises to
define their own custom queries and algorithms to gather and derive
enterprise-specific attributes that are deemed of interest to regular
enterprise operations.
In addition to collecting these attributes, metadata about the
attributes should also be collected which could include:
Data origin - where the data originated from
Data source - what provided the data
Date and time of collection - when the data was collected
3.3.1. SACM Use Case Alignment
This sub-step aligns with the Data Publication building block
capability because this section involves storage of endpoint
attributes within an enterprise Repository. This sub-step also
aligns with the Endpoint Characterization and Endpoint Target
Identification building block capabilities because it further
characterizes the endpoint through automated and possibly manual
means. There is direct alignment with the Endpoint Component
Inventory, Posture Attribute Identification, and Posture Attribute
Value Collection building block capabilities since the purpose of
this sub-step is to perform an initial inventory of the endpoint and
collect basic attributes and their values. Last, there is alignment
with the Collection Guidance Acquisition building block capabilities
as the inventory and collection of endpoint attributes would be
directed by some type of enterprise or third-party guidance.
Coffin, et al. Expires July 25, 2016 [Page 8]
Internet-Draft SACM Vuln Scenario January 2016
3.4. Implementation Examples
Within the SACM Architecture, the Internal and External Collector
components could be used to allow enterprises to collect posture
attributes that demonstrate compliance with enterprise policy.
Endpoints can be required to provide posture attributes, which may
include identification attributes to enable persistent
communications.
The SWID Message and Attributes for IF-M standard defines collection
and validation of software identities using the ISO Software
Identification Tag Standard. Using this standard, the identity of
all installed software including the endpoint operating system, could
be collected and used for later assessment.
The OVAL Definitions Model provides a data model that can be used to
specify what posture attributes to collect as well as their expected
values which can be used to drive an assessment.
The OVAL System Characteristics Model can be used to capture
information about an endpoint. The model is specifically suited to
expressing OS information, endpoint identification information (such
as IP and MAC addresses), and other endpoint metadata.
4. Vulnerability Description Data
The next step in the Vulnerability Assessment scenario begins after
vulnerability description data has been received and processed into a
form that can be used in the assessment of the enterprise. As a part
of the enterprise process for managing vulnerability description
data, the enterprise should store all received and processed
vulnerability description data in a Repository. The stored
vulnerability description data can be used and compared with later
vulnerability description data for the purpose of duplicate detection
and in some cases, guidance on how to handle similar issues.
All vulnerability description data should be assigned an internal
tracking ID by the enterprise as a first step as this helps
compensate for the fact that incoming vulnerability description data
might not have a global identifier when it is received, and might
never be assigned one.
High-level vulnerability description data metadata to store would
include:
o Ingest date and time - the date and time that the vulnerability
description data was received by the enterprise.
Coffin, et al. Expires July 25, 2016 [Page 9]
Internet-Draft SACM Vuln Scenario January 2016
o Date and time of vulnerability description data release (i.e.,
publication or disclosure date and time) - Some older
vulnerability description data may be ingested long after
publication. This can be useful when reviewing historical
enterprise information to (potentially) identify the period when a
particular endpoint was first assessed as vulnerable. Sometimes
this information will help to differentiate between similar
vulnerability description data.
o Version - the version or iteration of the vulnerability
description data according to the author, if applicable.
o External Vulnerability Description Data ID(s) (if applicable) -
any external or third-party IDs assigned to the vulnerability
description data should be tracked. There could be multiple IDs
in some cases (e.g., vendor bug id, global ID, discoverer's local
ID, third-party vulnerability database ID, etc.).
o Severity Score (if available) - these may be useful for later
mitigation prioritization.
In addition to the described metadata, the raw or original
vulnerability description data would be stored along with the
specific information extracted from it that is to be used in the
applicability and assessment process.
4.1. SACM Use Case Alignment
This step aligns with the Data Publication and Data Retrieval
building block capabilities because this section details storage of
vulnerability description data within an enterprise Repository and
later retrieval of the same.
4.2. Implementation Examples
The Common Vulnerability Reporting Framework (CVRF) is an XML-based
language that attempts to standardize the creation of vulnerability
report documentation. Using CVRF, the enterprise could create
automated tools based on the standardized schema which would obtain
the needed and relevant information useful for later assessments and
assessment results.
5. Endpoint Applicability and Assessment
When new vulnerability description data is received by the
enterprise, applicable enterprise endpoints must be identified and
assessed. Endpoints are first examined using the already obtained
pre-assessment data. If this is not sufficient to determine endpoint
Coffin, et al. Expires July 25, 2016 [Page 10]
Internet-Draft SACM Vuln Scenario January 2016
applicability, a secondary data collection for additional data and
attributes may be performed to determine status with regard to the
vulnerability description data.
5.1. Applicability
The applicability of an endpoint and its vulnerability status can, in
many cases, be determined entirely by the existence of a particular
version of installed software on the endpoint. This data may have
been collected in the pre-assessment data collection. If the
applicability and vulnerability status of an endpoint can be
determined entirely by the pre-collected data attribute set, no
further data collection is required.
Other cases may require specific data (i.e., file system attributes,
specific configuration parameters, etc.) to be collected for the
assessment of a particular vulnerability description data. In these
cases, a secondary, targeted vulnerability assessment is required.
Administrators may want to evaluate applicability to the
vulnerability description data iteratively. Specifically, the
process would compare against pre-collected data first (easy to do
and the data is stored in a Repository), and then if needed, query
endpoints that are not already excluded from applicability for
additional required data. (I.e., A "fast-fail" model). To do this,
the criteria for determining applicability must be separable, so that
some conclusions can be drawn based on the possession of partial
data.
5.1.1. SACM Use Case Alignment
This sub-step aligns with the Data Retrieval, Data Query, and Posture
Attribute Value Query building block capabilities because, in this
sub-step, the process is attempting to determine the vulnerability
status of the endpoint using the data that has previously been
collected.
5.2. Secondary Assessment
If the applicability and vulnerability status of an endpoint cannot
be determined by the pre-assessment data collection, a secondary and
targeted assessment of the endpoint will be required. A secondary
assessment may also be required in the case that data on-hand (either
from pre-assessment or from prior secondary assessments) is stale or
out-of-date.
The following data types and attributes are examples of what might be
required in the case of a secondary and targeted assessment:
Coffin, et al. Expires July 25, 2016 [Page 11]
Internet-Draft SACM Vuln Scenario January 2016
o Specific files and attributes - i.e., file name, versions, size,
write date, modified date, checksum, etc. Some vulnerabilities
may only be distinguishable through the presence or absence of
specific files or their attributes.
o Shared libraries - Some vulnerabilities will affect many products
across multiple vendors. In these cases the vulnerability may
apply to a shared library. Under these circumstances, product
versions may be less helpful than looking for the presence of one
or more specific files and their attributes.
o Other software configuration information (if applicable) - e.g.,
Microsoft Windows registry queries, Apple configuration profiles,
GConf, Proc filesystem, text configuration files and their
parameters, and the installation paths. Sometimes vulnerabilities
only affect certain software configurations and in some cases
these are not the default configurations. Certain configuration
attributes can be used to determine the current configuration
state.
Note that the secondary assessment described here does not need to be
a pull assessment that is initiated by the server. The secondary
assessment could also be part of a push to the server when the
endpoint detects a change to a vulnerability assessment baseline.
5.2.1. SACM Use Case Alignment
This sub-step aligns with the Data Publication building block
capability because this section details storage of endpoint
attributes within an enterprise Repository. The sub-step also aligns
with the Collection Guidance Acquisition building block capability
since the vulnerability description data (guidance) drives the
collection of additional endpoint attributes.
This sub-step aligns with the Endpoint Characterization (both manual
and automated) and Endpoint Target Identification building block
capabilities because it could further characterize the endpoint
through automated and possibly manual means. There is direct
alignment with the Endpoint Component Inventory, Posture Attribute
Identification, and Posture Attribute Value Collection building block
capabilities since the purpose of this sub-step is to perform
additional and more specific component inventories and collections of
endpoint attributes and their values.
Coffin, et al. Expires July 25, 2016 [Page 12]
Internet-Draft SACM Vuln Scenario January 2016
5.3. Implementation Examples
Within the SACM Architecture, the assessment task would be handled by
the Evaluator component. If pre-assessment data is used, this would
be stored on and obtained from a Data Store component.
Within the SACM Architecture, the Internal and External Collector
components could be used to allow enterprises to collect posture
attributes that demonstrate compliance with enterprise policy.
Endpoints can be required to provide posture attributes, which may
include identification attributes to enable persistent
communications.
The SWID Message and Attributes for IF-M standard defines collection
and validation of software identities using the ISO Software
Identification Tag Standard. Using this standard, all installed
software including the endpoint operating system could be collected
and stored for later assessment.
The OVAL Definitions Model provides a data model that can be used to
specify what posture attributes to collect as well as their expected
values which can be used to drive an assessment.
The OVAL System Characteristics Model can be used to capture
information about an endpoint. The model is specifically suited to
expressing OS information, endpoint identification information (such
as IP and MAC addresses), and other endpoint metadata.
The SACM Internal and External Attribute Collector components can be
used to allow enterprises to collect posture attributes that
demonstrate compliance with enterprise policy. Endpoints can be
required to provide posture attributes, which may include
identification attributes to enable persistent communications.
6. Assessment Results
Assessment results present the results of an assessment, along with
sufficient context so a human or machine can make the appropriate
response. This context might include a description of the issue
provided by the vulnerability description data, the endpoint
attributes that indicate applicability, or other information needed
to respond to the results of the assessment. Data in this step is
stored for auditing and forensic purposes.
The following details are important to track in assessment results.
Note that information may be "included" by providing pointers to
other records stored in a Repository (e.g., vulnerability description
data, endpoint data, etc.).
Coffin, et al. Expires July 25, 2016 [Page 13]
Internet-Draft SACM Vuln Scenario January 2016
o Date and time of assessment - The date and time that the
assessment was performed. To understand when the data was
compared against the vulnerability description data and what
conclusions were drawn.
o Data collection/attribute age - The age of the data used in the
assessment to make the endpoint status determination.
o Endpoint ID - The endpoint itself must be identified for tracking
results over time.
o Vulnerability description data ID(s) - May include both the
internally defined ID as well as one or more externally defined
IDs if they exist. The internally assigned ID allows linkage to
the correct vulnerability description data. If available,
external IDs provide a "pivot point" to additional external
information.
o Vulnerable software product(s) - Identifies the software products
on the endpoint that resulted in the endpoint being declared
applicable. Since some vulnerability description data identify
vulnerabilities in multiple products, this will help identify the
specific product (or products) found to be vulnerable in the
endpoint assessment.
o Endpoint vulnerability status - The endpoint status based on the
vulnerability description data. Does the vulnerability exist on
the endpoint?
o Vulnerability description - Not needed for automated assessment
but probably should be included for human review. The reason for
inclusion is to support the human user understanding of the
vulnerability assessment results within the application front-end
or interface.
o Vulnerability remediation - Similar to the above, remediation or
vendor patch information would be useful for a human response. In
many cases, this information may be a part of the description
information described above. Note that patch information may
change over time due to supercession of the vendor patches.
6.1. SACM Use Case Alignment
This step aligns with the Data Publication and Data Retrieval
building block capabilities because this section details storage of
vulnerability assessment results within an enterprise Repository and
later retrieval of the same.
Coffin, et al. Expires July 25, 2016 [Page 14]
Internet-Draft SACM Vuln Scenario January 2016
6.2. Implementation Examples
The OVAL Results Model provides a data model to encode the results of
the assessment, which could then be stored in a Repository and later
accessed. The assessment results described in this scenario could be
stored and later accessed using the OVAL Results Model. Note that
the use of the OVAL Results Model for sharing results is not
recommended per section 7.3 of the OVAL and the SACM Information
Model [draft-hansbury-sacm-oval-info-model-mapping-01].
Within the SACM Architecture, the generation of the assessment
results would occur in the Report Generator component. Those results
might then be moved to a Data Store component for later sharing and
retrieval as defined by SACM.
7. IANA Considerations
This memo includes no request to IANA.
8. Security Considerations
This document provides a core narrative that walks through an
automated enterprise vulnerability assessment scenario and is aligned
with SACM "Endpoint Security Posture Assessment: Enterprise Use
Cases" [RFC7632]. As a result, the security considerations for
[RFC7632] apply to this document. Furthermore, the vulnerability
description data may provide attackers with useful information such
as what software an enterprise is running on their endpoints. As a
result, organizations should properly protect the vulnerability
description data it ingests.***TODO IS THIS COVERED BY RFC7632???***
9. Informative References
[charter-ietf-sacm-01]
Security Automation and Continuous Monitoring, "Charter,
Version 1.0", July 2013.
[critical-controls]
Council on CyberSecurity, "Critical Security Controls,
Version 5.1".
[draft-hansbury-sacm-oval-info-model-mapping-01]
Security Automation and Continuous Monitoring, "OVAL and
the SACM Information Model", November 2015.
Coffin, et al. Expires July 25, 2016 [Page 15]
Internet-Draft SACM Vuln Scenario January 2016
[I-D.ietf-sacm-requirements]
Cam-Winget, N. and L. Lorenzin, "Secure Automation and
Continuous Monitoring (SACM) Requirements", draft-ietf-
sacm-requirements-11 (work in progress), November 2015.
[RFC7632] Waltermire, D. and D. Harrington, "Endpoint Security
Posture Assessment: Enterprise Use Cases", RFC 7632,
DOI 10.17487/RFC7632, September 2015,
<http://www.rfc-editor.org/info/rfc7632>.
Appendix A. Change Log
A.1. Changes in Revision 01
Clarification of the vulnerability description data IDs in sections 4
and 6.
Added "vulnerability remediation" to the Assessment Results and Data
Attribute Table and Definitions sections.
Added Implementation Examples to Endpoint Identification and Initial
(Pre-Assessment) Data Collection, Vulnerability Description Data,
Endpoint Applicability and Assessment, and Assessment Results
sections.
Added an example to vulnerability description data in the scope
section.
Added a sentence to clarify vulnerability description data definition
in the scope section.
Added data repository example for long-term storage scope item.
Added sentence to direct reader to examples of basic system
information in endpoint identification section.
Split the examples of information to collect in the pre-assessment
collection section into a basic and advanced list.
Added examples of data stored in the repository in the Assessment
Results section.
Added sentence for human-assigned attributes in the Future Work
section.
Replaced "vulnerability report" to "vulnerability description data"
because the term report was causing confusion. Similarly, replaced
"assessment report" with "assessment results".
Coffin, et al. Expires July 25, 2016 [Page 16]
Internet-Draft SACM Vuln Scenario January 2016
Replaced "Configuration Management Database (CMDB)" with "Repository"
which is SACM's term for a data store.
Replaced endpoint "Role" with "Purpose" because "Role" is already
defined in SACM. Also, removed "Function" because it too is already
defined in SACM.
Clarified that the document does not try to define a normalized data
format for vulnerability description data although it does not
preclude the creation of such a format.
Included additional examples of software configuration information.
Clarified the section around endpoint identification to make it clear
designation attributes used to correlate and identify endoints are
both persistent and unique. Furthermore, text was added to explain
how the persistency of attributes may vary. This was based on
knowledge gained from the Endpoint ID Design Team.
Updated the Security Considerations section to mention those
described in [RFC7632].
Removed text around Bring Your Own Device (BYOD). While important,
BYOD just adds complexity to this initial draft. BYOD should be
addressed in a later revision.
Merged the list of "basic endpoint information" and the list of
"human-assigned endpoint attributes" as both represent data we want
to collect about an endpoint. Whether or not that data is natively
available on the endpoint for collection or assigned by a human,
computed, or derived from other data which may or may not be
available on the endpoint for collection seems arbitrary. With this
scenario, we primarily care about expressing information needs rather
than how the information is collected or from where.
Appendix B. Continuous Vulnerability Assessment
It is not sufficient to perform a single assessment when
vulnerability description data is published without any further
checking. Doing so does not address the possibility that the
reported vulnerability might be introduced to the enterprise
environment after the intial assessment completes. For example, new
endpoints can be introduced to the environment which have old
software or are not up-to-date with patches. Another example is
where unauthorized or obsolete software is installed on an existing
endpoint by enterprise users after vulnerability description data and
initial assessment has taken place. Moreover, enterprises might not
wish to, or be able to, assess all vulnerability description data
Coffin, et al. Expires July 25, 2016 [Page 17]
Internet-Draft SACM Vuln Scenario January 2016
immediately when they come in. Conflicts with other critical
activities or limited resources might mean that some alerts,
especially those that the enterprise deems as "low priority", are not
used to guide enterprise assessments until sometime after the initial
receipt.
The scenario above describes a single assessment of endpoints.
However, it does not make any assumptions as to when this assessment
occurs relative to the original receipt of the vulnerability
description data that led to this assessment. The assessment could
immediately follow ingest of the vulnerability description data,
could be delayed, or the assessment might represent a reassessment of
some vulnerability description data against which endpoints had
previously been assessed. Moreover, the scenario incorporates long-
term storage of collected data, vulnerability description data, and
assessment results in order to facilitate meaningful and ongoing
reassessment.
Appendix C. Priority
Priorities associated with the vulnerability description data,
assessment results, and any remedy is important, but is treated as a
separate challenge and, as such, has not been integrated into the
description of this scenario. Nevertheless, it is important to point
out and describe the use of priorities in the overall vulnerability
description data scenario as they separable issues with their own
sets of requirements.
Priority in regard to vulnerability description data, can be viewed
in a couple of different ways within an enterprise. The assessment
prioritization involves prioritization of the vulnerability
description data assessment process. This determines what
vulnerability description data is assessed, and in what order it is
assessed in. For instance, a vulnerability affecting an operating
system or application used throughout the enterprise would likely be
prioritized higher than a vulnerability in an application which is
used only on a few, low-criticality endpoints.
The prioritization of remedies relates to the enterprise remediation
and mitigation process based on the discovered vulnerabilities. Once
an assessment has been performed and applicable endpoints identified,
enterprise vulnerability managers must determine where to focus their
efforts to apply appropriate remedies. For example, a vulnerability
that is easily exploitable and which can allow arbitrary code
execution might be remedied before a vulnerability that is more
difficult to exploit or which just degrades performance.
Coffin, et al. Expires July 25, 2016 [Page 18]
Internet-Draft SACM Vuln Scenario January 2016
Some vulnerability description data include severities and/or other
information that places the vulnerability in context. This
information can be used in both of the priority types discussed
above. In other cases, enterprise administrators may need to
prioritize based only on what they know about their enterprise and
the description provided in the vulnerability description data.
Examples of data attributes specific to priority of assessments and/
or remedies include (but not limited to) the following:
o Enterprise - defined purpose of the device, criticality of the
device, exposure of the device, etc.
o Severity attributes - A rating or score that attempts to provide
the level of severity or criticality associated with a given
vulnerability.
o Cyber threat intelligence - information such as tactics,
techniques, and procedures of threat actors, indicators of
compromise, incidents, courses of action, etc. that help the
enterprise understand relevant threats and how to detect,
mitigate, or respond to them.
Appendix D. Data Attribute Table and Definitions
D.1. Table
The following table maps all major data attributes against each major
process where they are used.
+--------------+------------+--------------+-------------+----------+
| | vulnerabil | Endpoint Ide | Endpoint Ap | Assessme |
| | ity descri | ntification | plicability | nt |
| | ption data | and Initial | and | Results |
| | | (Pre- | Assessment | |
| | | Assessment) | | |
| | | Data | | |
| | | Collection | | |
+--------------+------------+--------------+-------------+----------+
| *Endpoint* | | | | |
+--------------+------------+--------------+-------------+----------+
| Collection | | X | X | |
| date/time | | | | |
+--------------+------------+--------------+-------------+----------+
| Endpoint | | X | X | |
| type | | | | |
+--------------+------------+--------------+-------------+----------+
| Hardware ver | X | X | X | |
Coffin, et al. Expires July 25, 2016 [Page 19]
Internet-Draft SACM Vuln Scenario January 2016
| sion/firmwar | | | | |
| e | | | | |
+--------------+------------+--------------+-------------+----------+
| Operating | X | X | X | |
| system | | | | |
+--------------+------------+--------------+-------------+----------+
| Operating | X | X | X | |
| system | | | | |
| attributes | | | | |
| (e.g., | | | | |
| version, | | | | |
| service pack | | | | |
| level, | | | | |
| edition, | | | | |
| etc.) | | | | |
+--------------+------------+--------------+-------------+----------+
| Installed | X | X | X | X |
| software | | | | |
| name | | | | |
+--------------+------------+--------------+-------------+----------+
| Installed | X | X | X | X |
| software | | | | |
| attributes | | | | |
| (e.g., | | | | |
| version, | | | | |
| patch level, | | | | |
| install | | | | |
| path, etc.) | | | | |
+--------------+------------+--------------+-------------+----------+
| Open ports/s | X | X | X | |
| ervices | | | | |
+--------------+------------+--------------+-------------+----------+
| Operating | X | X | X | |
| system | | | | |
| optional | | | | |
| component | | | | |
| inventory | | | | |
+--------------+------------+--------------+-------------+----------+
| Location | | X | | X |
+--------------+------------+--------------+-------------+----------+
| Purpose | | X | | X |
+--------------+------------+--------------+-------------+----------+
| Criticality | | X | | X |
+--------------+------------+--------------+-------------+----------+
| File system | X | | X | |
| attributes | | | | |
| (e.g., | | | | |
| versions, | | | | |
Coffin, et al. Expires July 25, 2016 [Page 20]
Internet-Draft SACM Vuln Scenario January 2016
| size, write | | | | |
| date, | | | | |
| modified | | | | |
| date, | | | | |
| checksum, | | | | |
| etc.) | | | | |
+--------------+------------+--------------+-------------+----------+
| Shared | X | | X | |
| libraries | | | | |
+--------------+------------+--------------+-------------+----------+
| Other | X | | X | |
| software con | | | | |
| figuration | | | | |
| information | | | | |
+--------------+------------+--------------+-------------+----------+
| *External vu | | | | |
| lnerability | | | | |
| description | | | | |
| data* | | | | |
+--------------+------------+--------------+-------------+----------+
| Ingest Date | X | | X | |
+--------------+------------+--------------+-------------+----------+
| Date of | X | | X | |
| Release | | | | |
+--------------+------------+--------------+-------------+----------+
| Version | X | | X | |
+--------------+------------+--------------+-------------+----------+
| External | X | | X | X |
| vuln ID | | | | |
+--------------+------------+--------------+-------------+----------+
| Severity | | | | X |
| Score | | | | |
+--------------+------------+--------------+-------------+----------+
| *Assessment | | | | |
| Results* | | | | |
+--------------+------------+--------------+-------------+----------+
| Date of | | | X | X |
| assessment | | | | |
+--------------+------------+--------------+-------------+----------+
| Date of data | | X | X | X |
| collection | | | | |
+--------------+------------+--------------+-------------+----------+
| Endpoint ide | | X | X | X |
| ntification | | | | |
| and/or | | | | |
| locally | | | | |
| assigned ID | | | | |
+--------------+------------+--------------+-------------+----------+
Coffin, et al. Expires July 25, 2016 [Page 21]
Internet-Draft SACM Vuln Scenario January 2016
| Vulnerable | X | X | X | X |
| software | | | | |
| product(s) | | | | |
+--------------+------------+--------------+-------------+----------+
| Endpoint vul | | | X | X |
| nerability | | | | |
| status | | | | |
+--------------+------------+--------------+-------------+----------+
| Vulnerabilit | X | | | X |
| y | | | | |
| description | | | | |
+--------------+------------+--------------+-------------+----------+
| Vulnerabilit | X | | | X |
| y | | | | |
| rememdiation | | | | |
+--------------+------------+--------------+-------------+----------+
Table 1: Vulnerability Assessment Attributes
D.2. Definitions
Endpoint
o Collection date/time - the date and time of data collection
o Endpoint type - the device type of the endpoint (e.g., standard
computer, printer, router, mobile device, tablet, etc.)
o Hardware version/firmware - the hardware or firmware version if
applicable (e.g., BIOS version, firmware revision, etc.)
o Operating system - Operating system name
o Operating system attributes - Operating system high-level
attributes (e.g., version, service pack level, edition, etc.).
Would not include configuration details.
o Installed software name - List of all installed software packages
(i.e., software inventory). May or may not include software
installed by the operating system.
o Installed software attributes - Software high-level attributes
(e.g., version, patch level, install path, etc.). Would not
include configuration details.
o Open ports/enabled services - Listening network ports (e.g., TCP,
UDP, etc.) as well as services that are starting, running,
suspended, or enabled to run pending some event.
Coffin, et al. Expires July 25, 2016 [Page 22]
Internet-Draft SACM Vuln Scenario January 2016
o Operating system optional component inventory - Operating system
specific components and software (when NOT already included in the
general software inventory)
o Location - The physical location of an enterprise endpoint (e.g.,
department, room, etc.)
o Purpose - describes how the endpoint is used within the enterprise
(e.g., end user system, database server, public web server, etc.)
o Criticality - An enterprise-defined rating (possibly a score) that
helps determine the criticality of the endpoint. If this endpoint
is attacked or lost, what is the impact to the overall enterprise?
o File system attributes - Attributes that describe the file or
directory (e.g., versions, size, write date, modified date,
checksum, etc.)
o Shared libraries - libraries that can be used by and installed
with many different software applications. A shared library
vulnerability could affect multiple software applications in the
same way.
o Other software configuration information - operating system or
software application configuration attributes that go beyond that
basic information already captured (e.g., Microsoft Windows
registry, Apple configuration profiles, GConf, Proc filesystem,
text configuration files and their parameters, and the
installation paths.)
External vulnerability description data
o Ingest Date - the date that the vulnerability description data was
received by the enterprise.
o Date of Release - publication or disclosure date of the
vulnerability description data
o Version - the version or iteration of the vulnerability
description data according to the author, if applicable.
o External vuln ID - external or third-party IDs assigned to the
vulnerability description data. Could be multiple IDs in some
cases (e.g., vendor bug id, global ID, discoverer's local ID,
third-party vulnerability database ID, etc.).
Coffin, et al. Expires July 25, 2016 [Page 23]
Internet-Draft SACM Vuln Scenario January 2016
o Severity Score - the severity of the vulnerability description
data according to the vulnerability description data author, if
applicable.
Assessment Results
o Date of assessment - The date that the assessment was performed
against an endpoint.
o Date of data collection - The age of the data used in the
assessment to make the endpoint status determination.
o Endpoint identification and/or locally assigned ID - The ID
assigned to the enterprise endpoint. Must be assigned for
tracking results over time.
o Vulnerable software product(s) - The vulnerable software products
identified as being installed on the endpoint.
o Endpoint vulnerability status - Overall vulnerability status of
the enterprise endpoint (i.e., Pass or Fail)
o Vulnerability description - A human-consumable description of a
vulnerability. Supports the human user understanding of the
vulnerability assessment results within an application front-end
or user interface.
o Vulnerability remediation - The fix, workaround, or patch
information for a vulnerability. This information may be a part
of the vulnerability description described previously. Note that
this information can change over time due to vendor patch
supercession.
Appendix E. Alignment with Other Existing Works
E.1. Critical Security Controls
The Council on CyberSecurity's Critical Security Controls
[critical-controls] includes security controls for a number of use
scenarios, some of which are covered in this document. This section
documents the alignment between the Council's controls and the
relevant elements of the scenario.
E.1.1. Continuous Vulnerability Assessment
"CSC 4: Continuous Vulnerability Assessment and Remediation," which
is described by the Council on CyberSecurity as "Continuously
acquire, assess, and take action on new information in order to
Coffin, et al. Expires July 25, 2016 [Page 24]
Internet-Draft SACM Vuln Scenario January 2016
identify vulnerabilities, remediate, and minimize the window of
opportunity for attackers." The scenario described in this document
is aligned with CSC 4 in multiple ways:
CSC 4-1 applies to this scenario in that it calls for running
regular, automated scanning to deliver prioritized lists of
vulnerabilities with which to respond. The scenario described in
this document is intended to be executed on a continuous basis, and
the priorities of both vulnerability description data and the remedy
of vulnerabilities are discussed in the Priority section earlier in
this document.
This scenario assumes that the enterprise already has a source for
vulnerability description data as described in CSC 4-4.
Both CSC 4-2 and 4-7 are made possible by writing information to a
Repository since this makes previously collected data available for
later analysis.
While this scenario does not go into the details of how
prioritization would be calculated or applied, it does touch on some
of the important ways in which prioritization would impact the
endpoint assessment process in the Priority section. As such, the
Priority section aligns with CSC 4-10, which deals with vulnerability
priority. Vulnerability priority in this scenario is discussed in
terms of the vulnerability description data priority during receipt,
as well as the vulnerability priority with regards to remedies.
The described scenario does not address the details of applying a
remedy based on assessment results. As such, CSC 4-5, 4-8, and 4-9,
which all deal with mitigations and patching, are out of scope for
this work. Similarly, CSC 4-3 prescribes performing scans in
authenticated mode and CSC 4-6 prescribes monitoring logs. This
scenario does not get into the means by which data is collected,
focusing on "what" to collect rather than "how", and as such does not
have corresponding sections, although the procedures described are
not incompatible with either of these controls.
The CSC 4 System Entity Relationship diagram and numbered steps
directly align with the scenario described in this document with the
exception of step 7 (patch response). Steps 1 -6 in CSC 4 describe
the overall process for vulnerability management starting with
obtaining the vulnerability description data from the source in Step
1, to producing assessment results in step 6.
Coffin, et al. Expires July 25, 2016 [Page 25]
Internet-Draft SACM Vuln Scenario January 2016
E.1.2. Hardware and Software Inventories
This scenario is also aligned with, and describes a process for,
collecting and maintaining hardware and software inventories, which
are covered by the Council on CyberSecurity CSC 1 "Inventory of
Authorized and Unauthorized Devices" and CSC 2 "Inventory of
Authorized and Unauthorized Software." This scenario documents a
process that is specific to collecting and maintaining hardware and
software data attributes for vulnerability assessment purposes, but
the collection of the hardware attributes and software inventory
documented in the Endpoint Data Collection section that follows can
also be used for the purpose of implementing authorized and
unauthorized hardware and software management processes (e.g.,
scanning tools looking for unauthorized software). Moreover, the
ability to accurately identify endpoints and, to a lesser degree,
applications is integral to effective endpoint data collection and
vulnerability management.
The Endpoint Data Collection section does not have coverage for the
specific details described in CSC 1 and 2 as they are different
processes and would be out-of-scope of this scenario, but the section
does provide the data necessary to support the controls.
The Endpoint Identification and Endpoint Data Collection sections
within this scenario align with CSC 1-1 and 1-4 by identifying
enterprise endpoints and collecting their hardware and network
attributes. The Endpoint Data Collection section aligns with and
supports CSC 2-3 and 2-4 by defining a software inventory process and
a method of obtaining operating system and file system attributes.
The rest of the items from CSC 1 and 2 deal with implementation
details and would be out-of-scope for this document.
CSC 2-9 describes the use of a software ID tag in XML format. SWID
tags (https://en.wikipedia.org/wiki/ISO/IEC_19770) would also be a
possible implementation for the Endpoint Data Collection section
described in this scenario.
Appendix F. SACM Usage Scenarios
The SACM "Endpoint Security Posture Assessment: Enterprise Use Cases"
document ([RFC7632]) defines multiple usage scenarios that are meant
to provide examples of implementing the use cases and building block
capabilities. Below is a brief summary of some of these usage
scenarios and how this document aligns and/or adds additional value
to the identified usage scenarios.
o Automated Checklist Verification (2.2.2) - "An enterprise operates
a heterogeneous IT environment. They utilize vendor-provided
Coffin, et al. Expires July 25, 2016 [Page 26]
Internet-Draft SACM Vuln Scenario January 2016
automatable security configuration checklists for each operating
system and application used within their IT environment. Multiple
checklists are used from different vendors to ensure adequate
coverage of all IT assets." The usage scenario, as defined in the
RFC, is targeted at the checklist level and can be interpreted as
being specific to endpoint configuration. There is mention of
patch assessment and vulnerability mitigation, but the usage
scenario could be expanded upon by including vulnerability
verification. Replacing the idea of a checklist in the SACM usage
scenario with vulnerability would allow the usage scenario to
align almost exactly with the scenario described in this document.
Instead of collecting automatable security configuration
checklists, the enterprise would collect automatable vulnerability
description data available from the vendor as described or
possibly from other interested third-parties.
o Detection of Posture Deviations (2.2.3) - "An enterprise has
established secure configuration baselines for each different type
of endpoint within their IT environment. When an endpoint
connects to the network, the appropriate baseline configuration is
communicated to the endpoint. Once the baseline has been
established, the endpoint is monitored for any change events
pertaining to the baseline on an ongoing basis. When a change
occurs to posture defined in the baseline, updated posture
information is exchanged. When the endpoint detects a posture
change, an alert is generated identifying the specific changes in
posture." This usage scenario would support the concept of
endpoints signaling or alerting the enterprise to changes in the
posture relates to endpoint vulnerabilities in the same way that
it would for configurations. Replacing the idea of a checklist
with vulnerability description data allows the SACM usage scenario
and the scenario described in this document to align in their
objectives.
o Asynchronous Compliance/Vulnerability Assessment at Ice Station
Zebra (2.2.5) - "An isolated arctic IT environment that is
separated from the main university network. The only network
communications are via an intermittent, low-speed, high-latency,
high-cost satellite link. Remote network admins will need to show
continued compliance with the security policies of the university,
the government, and the provider of the satellite network, as well
as keep current on vulnerability testing." This SACM usage
scenario describes vulnerability assessment and aligns well with
the vulnerability scenario described in this document. The
endpoint assets are identified and associated data is published in
a Repository. Vulnerability description data is collected and
saved in a Repository as it is released. The vulnerability
description data is queued for later assessment, then the
Coffin, et al. Expires July 25, 2016 [Page 27]
Internet-Draft SACM Vuln Scenario January 2016
assessment results and vulnerability description data are stored
after assessment. The only real difference in this SACM usage
scenario is the timing of the assessments. The scenario described
within this document would have no problems adjusting to the
timing of this SACM usage scenario or anything similar.
Appendix G. SACM Requirements and Charter - Future Work
In the course authoring this document, some additional considerations
for possible future work were noted. The following points were taken
from the SACM Requirements [I-D.ietf-sacm-requirements], SACM Charter
[charter-ietf-sacm-01], and SACM Use Cases ([RFC7632]) documents and
represent work that may be necessary to support the tasks or goals of
SACM going forward.
o The SACM requirements mentions "Result Reporting" with
applications but no detail around what the assessment results data
set should include. In the case of vulnerability assessment
results, context is important and details beyond just a Pass or
Fail result are needed in order to take action. A good example of
this might be the Priority of the vulnerability itself and how
many systems it affects within the enterprise. With this in mind,
it might be worthwhile to investigate a minimum data set or schema
for assessment results. The concern here is with vulnerability
description data, but this could apply to other enterprise
processes as well.
o The "Human-assigned endpoint attributes" mentioned previously in
this scenario are touched on in the SACM use cases, but the topic
could probably be explored in much more depth. Enterprise policy
and behaviors could be greatly influenced by endpoint attributes
such as locations, how the endpoint is used, and criticality.
When and how these data attributes are collected, as well as what
the minimum or common set might look like, would be good topics
for future related SACM work. In addition, the storage of these
attributes could be central (stored in a data repository) or they
could be assigned and stored on the endpoints themselves.
Authors' Addresses
Christopher Coffin
The MITRE Corporation
202 Burlington Road
Bedford, MA 01730
USA
Email: ccoffin@mitre.org
Coffin, et al. Expires July 25, 2016 [Page 28]
Internet-Draft SACM Vuln Scenario January 2016
Brant Cheikes
The MITRE Corporation
202 Burlington Road
Bedford, MA 01730
USA
Email: bcheikes@mitre.org
Charles Schmidt
The MITRE Corporation
202 Burlington Road
Bedford, MA 01730
USA
Email: cmschmidt@mitre.org
Daniel Haynes
The MITRE Corporation
202 Burlington Road
Bedford, MA 01730
USA
Email: dhaynes@mitre.org
Jessica Fitzgerald-McKay
Department of Defense
9800 Savage Road
Ft. Meade, Maryland
USA
Email: jmfitz2@nsa.gov
David Waltermire
National Institute of Standards and Technology
100 Bureau Drive
Gaithersburg, Maryland 20877
USA
Email: david.waltermire@nist.gov
Coffin, et al. Expires July 25, 2016 [Page 29]
