Internet Engineering Task Force Nevil Brownlee
INTERNET-DRAFT The University of Auckland
Valid for six months Erik Guttman
Sun Microsystems
March 1997
Expectations for Security Incident Response
<draft-ietf-grip-framework-irt-04.txt>
Status of this Memo
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Abstract
The purpose of this document is to express the general Internet
community's expectations of Security Incident Response Teams. It
is not possible to define a set of requirements that would be
appropriate for all teams, but it is possible and helpful to
list and describe the general set of topics and issues which
are of concern and interest to constituent communities.
SIRT constituents have a legitimate need and right to fully understand
the policies and procedures of "their" Security Incident Response Team.
One way to support this understanding is to supply detailed information
which users may consider, in the form of a formal template completed by
the SIRT. An outline of such a template and a filled in example is
provided.
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Table of Contents
1 Introduction 1
2 Scope..............................................................3
2.1 Publishing a SIRT Policies and Procedures .....................4
2.2 Relationships between different SIRTs .........................5
2.3 Establishing Secure Communications ............................6
3 Information, Policies and Procedures...............................7
3.1 Contact Information ...........................................8
3.2 Document Updates ..............................................9
3.3 Charter .......................................................9
3.3.1 Mission Statement.......................................10
3.3.2 Constituency............................................10
3.3.3 Sponsoring Organization / Affiliation...................10
3.3.4 Authority...............................................11
3.4 Policies .....................................................11
3.4.1 Types of Incidents and Level of Support.................11
3.4.2 Co-operation and Interaction with other Organizations...12
3.4.3 Reporting and Disclosure................................13
3.4.4 Communication and Authentication........................14
3.4.5 Point of Customer Contacts..............................14
3.5 Services .....................................................15
3.6 Incident Reporting Forms .....................................15
3.7 Disclaimers ..................................................16
4 Appendix A: Glossary of Terms 17
5 Appendix B: Related Material 18
6 Appendix C: Known Security Incident Response Teams 19
7 Appendix D: Outline for SIRT Template 21
8 Appendix E: Example - 'filled-in' Template for a SIRT 22
9 References 29
10 Security Considerations 29
11 Authors' Addresses 29
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1 Introduction
The GRIP Working Group was formed to create a document that describes
the community's expectations of security incident response teams
(SIRTs). Although the need for such a document originated in the
general Internet community, the expectations expressed should also
closely match those of more restricted communities.
In the past there have been misunderstandings regarding what to expect
from SIRTs. The goal of this document is to provide a framework for
presenting the important subjects (related to incident response) that
are of concern to the community.
Before continuing, it is important to clearly understand what is meant
by the term "Security Incident Response Team." For the purposes of
this document, a SIRT is a team that performs, coordinates, and supports
the response to security incidents that involve sites within a defined
constituency (see Appendix A for a more complete definition). Any
group calling itself a SIRT for a specific constituency must therefore
react to reported security incidents, and to threats to "their"
constituency in ways which the specific community agrees to be in its
general interest.
Since it is vital that each member of a constituent community be
able to understand what is reasonable to expect of their team, A SIRT
should make it clear who belongs to their constituency and define the
services the team offers to the community. Additionally, each SIRT
should publish its policies and operating procedures. Similarly, these
same constituents need to know what is expected of them in order for
them to receive the services of their team. This requires that the
team also publish how and where incidents should be reported.
This document details a template which will be used by SIRTs to
communicate this information to their constituents. The constituents
should certainly expect a SIRT to provide the services they describe in
the completed template.
It must be emphasised that without active participation from users, the
effectiveness of the SIRT's services can be greatly diminished. This
is particularly the case with reporting. At a minimum, users need to
know that they should report security incidents, and know how and where
they should report them to.
Many computer security incidents originate outside local community
boundaries and affect inside sites, others originate inside the local
community and affect hosts or users on the outside. Often, therefore,
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the handling of security incidents will involve the cooperation of
multiple sites and potentially multiple SIRTs. The coordination of
activities across communities and organization requires that the
parties understand who they are dealing with, and what sort of policies
they have in place.
Many computer security incidents originate outside local community
boundaries and affect inside sites, others originate inside the local
community and affect hosts or users on the outside. Often, therefore,
the handling of security incidents will involve multiple sites and
potentially multiple SIRTs. Resolving these incidents will require
cooperation between individual sites and SIRTs, and between SIRTs.
Constituent communities need to know exactly how their SIRT will be
working with other SIRTs and organizations outside their constituency,
and what information will be shared.
The rest of this document describes the set of topics and issues that
SIRTs need to elaborate for their constituents. However, there is no
attempt to specify the "correct" answer to any one topic area. Rather,
each topic is discussed it terms of what that topic means. For example,
five types of policy statements are listed (representing those policies
of interest to the community), but the content of any one of them will
necessarily be specific to a given team.
Chapter two provides an overview of three major areas: The publishing
of information by a response team, the definition of the response
team's relationship to other response teams and the need for secure
communications. Chapter three describes in detail all the types of
information that the community needs to know about their response team.
These topics are condensed into an outline template for ease of use by
the community, and is found in Appendix D. This template can be used
by constituents to elicit information from their SIRT, and it provides
criteria with which to measure their team's performance.
It is the working group's sincere hope that through the clarification
of the topics in this document, understanding between the community
and its SIRTs will be increased.
2 Scope
The interactions between a constituent community and an incident
response team require first that the community understands the
policies and procedures of the response team. Second, since many
response teams collaborate to handle incidents, the community must
also understand the relationship between their response team and
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other teams. Finally, many interactions will take advantage of
existing public infrastructures and the community needs to know how
those communications are going to be protected. Each of these subjects
will be described in more detail in the following three sections.
2.1 Publishing a SIRT Policies and Procedures
Each user who has access to a Security Incident Response Team should
know as much as possible about services of and interactions with this
team long before he or she actually needs them.
A clear statement of the policies and procedures of a SIRT helps the
constituent understand how best to report incidents and what support to
expect afterwards. Will the SIRT assist in resolving the incident?
Will it provide help in avoiding incidents in the future? Clear
expectations, particularly of the limitations of the services provided
by a SIRT, will make interaction with it more efficient and effective.
There are different kinds of response teams. Some that have very
broad constituencies (e.g., CERT Coordination Center and the Internet),
others that have more bounded constituencies (e.g., DFN-CERT, CIAC),
and still others that have very restricted constituencies (e.g.,
commercial response teams, corporate response teams). Regardless of
the type of response team, the constituency supported by it must be
knowledgeable about the team's policies and procedures. Therefore, it
is mandatory that response teams publish such information to their
constituency.
As a SIRT provides a service to a this clearly defined constituency,
it should communicate all necessary information about its policies
and services in a suitable form. It is important to understand that
not all policies and procedures must be publicly available. For
example, it is not necessary to understand the internal operation of
a team in order to interact with it, as when reporting an incident or
receiving guidance on how to analyze or secure one's systems.
In the past, some teams supplied a kind of Operational Framework,
others provided Frequently Asked Questions (FAQ), while still
others wrote papers for distribution at user conferences or sent
newsletters.
Another efficient way to communicate the relevant information to all
concerned, not only constituents but also other teams or organizations,
would be for each SIRT to publish its guidelines and procedures on its
own information server. This would allow constituents to easily access
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it, although this does not address the problem of how a constituent or
will find "his" or "her" team. People within the constituency have to
discover that there is a SIRT "at their disposal." It is foreseen that
completed SIRT templates will soon become searchable by modern search
engines. This will aid in distributing information about the existence
of SIRTs and basic information required to approach them.
It would be very useful to have a central repository containing all the
completed SIRT templates. No such repository presently exists. This
might change in the future.
Regardless of the source from which the information is retrieved,
the user of the template must check its authenticity. It is highly
recommended that such vital documents be protected by digital
signatures. These will allow user can verify that the template
was indeed published by the SIRT and that it has not been modified
thereafter. This document assumes the reader has familiarity with
the proper use of digital signatures to determine whether a document
is authentic.
2.2 Relationships between different SIRTs
In some cases a SIRT may be able to operate effectively on its own
and in close cooperation with its constituency. But with todays
international networks it is much more likely that most of the
incidents handled by a SIRT will involve parties external to its
constituency. Therefore the team will need to interact with other
SIRTs and sites outside their constituency.
The constituent community should be clear about the nature and
extent of this collaboration, as very sensitive information about
individual constituents may be disclosed in the process.
Such interactions could include asking other teams for advice,
disseminating knowledge of problems and working cooperatively
to resolve a security incident effecting one or more of the SIRTs'
constituencies.
In establishing relationships to support such interactions, SIRTs will
need to decide what kinds of agreements can exist between them so as to
share yet safeguard information, whether this relationship can be
disclosed, and if so to whom.
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Note that there is a difference between a peering agreement, where the
SIRTs involved agree to work together and share information, and simple
co-operation, where a SIRT (or any other organization) simply contacts
another SIRT and asks for help or advice.
Although the establishing of such relationships is very important and
affect the ability of a SIRT to support its constituency, it is up to
the teams involved to decide about the details. It is beyond the scope
of this document to make recommendations for this process. But the
same set of information used to set expectations for a user community
regarding sharing of information will help other parties to understand
the objectives and services of a specific SIRT, supporting a first
contact.
2.3 Establishing Secure Communications
Once one party has decided to share information with another party, or
two parties have agreed to share information or work together - as
required for the coordination of Security Incident Response - all
parties involved need secure communications channels. ("Secure" hereby
relates to the protected transmission of information shared between
different parties and not the appropriate use of the information by the
parties.)
The goals of secure communication are:
- Confidentiality:
Can somebody else access the content of the communication?
- Integrity:
Can somebody else manipulate the content of the communication?
- Authenticity:
Am I communicating with the "right" person?
It is very easy to send forged e-mail, and not hard to establish a
(false) identity by telephone. Cryptographic techniques, for example
Pretty Good Privacy (PGP) or Privacy Enhanced Mail (PEM) can provide
effective ways of securing e-mail. With the correct equipment it is
also possible to secure telephone communication. But before using such
mechanisms, both parties need the "right" infrastructure, which is to
say preparation in advance. The most important preparation is ensuring
the authenticity of the cryptographic keys used in secure communication:
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- Public keys (for techniques like PGP and PEM):
Because they are accessible through the internet, they must be
authenticated before usage. While PGP relies on a
"Web of Trust" - users sign the keys of other users - PEM relies
on a hierarchy - certification authorities sign the keys of users.
- Secret keys (for techniques like DES and PGP/conventional
encryption): Because they must be known to sender and receiver,
they must be exchanged before the communication via a secure
channel.
Communication is critical for all aspects of incident response. A team
can best support the use of the above-mentioned techniques by gathering
all relevant information, in a consistent way. Specific requirements
(like calling a specific number for checking the authenticity
of keys) should be explained right away. SIRT templates provide a
standardized vehicle for delivering this information.
It is beyond the scope of this document to address all the technical
and administrative problems of secure communications. The point is
that response teams must support and use a method to secure the
communications between themselves and their constituents (or other
response teams). Whatever the mechanism is, the level of protection
it provides must be acceptable to the constituent community.
3 Information, Policies and Procedures
In chapter 2, it was mentioned that the policies and procedures of a
response team need to be published to their constituent community.
In this chapter we will list all the types of information that the
community needs to receive from its response team. How this
information is communicated to a community will differ from team to
team, as will the specific information content. The intent here is
to clearly describe the various kinds of information that a
constituent community expects from its response team.
To make it easier to understand all issues and topics relevant to the
interaction of constituents with "their" SIRT, we suggest that a SIRT
publish all information, policies and procedures addressing their
constituency as a document, following template given in Appendix D.
The template structure arranges items, making it easy to supply
specific information, was done for the example in Appendix E. While
no recommendations are made as to what a SIRT should adopt for their
policy or procedures, different possibilities are outlined to give some
examples. The most important thing is that a SIRT has a policy and that
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that those who interact with the SIRT can obtain and understand it.
As always, not every aspect for every environment and/or team can
be covered. This outline should be seen as a suggestion. Each team
should feel free to include whatever they think is necessary for
supporting their constituency.
3.1 Contact Information
Full details of how to contact the SIRT should be listed here, although
this might be very different for different teams. Some might choose to
restrict the availability of names of all team members. No further
clarification is given when the meaning of the item can be assumed.
- Name of the SIRT
- Mailing Address
- Time zone This is useful for coordinating
incidents which cross time zones.
- Telephone number
- Facsimile number
- Other telecommunication Some teams might provide secure
voice communication (e.g. STU III).
- Electronic mail address
- Public keys and encryption The use of specific techniques
depends on the ability of the
communication partners to have
access to programs, keys and so on.
Relevant information should be
outlined so users can determine
if and how they can make use of
secure communication while
interacting with the SIRT.
- Team members
- Other information The operating hours and holiday
schedule should be provided here.
Is there a 24 hour hotline? Is
there any specific customer contact
info? (See also section 3.4.5).
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3.2 Document Updates
Details of a SIRT change with time, so the completed template must
indicate when it was last changed. Additionally, information should be
provided to learn about how to find out about future updates. Without
this, it is inevitable that misunderstandings and misconceptions will
arise over time; an outdated document will do more harm than good.
- Date of last update This should be sufficient to allow
anyone interested to evaluate the
currency of the template.
- Distribution list Mailing lists are a convenient
mechanism to distribute up-to-date
information to a large number of
users. A team can decide to use its
own or an already existing list to
notify users whenever the document
changes. The list might normally
cover the constituency and any other
groups the SIRT has frequent
interactions with.
Digital signatures should be used
for update messages sent by a SIRT.
- Location of the document The location where a current version
of the document should be accessible
through a team's online information
services. Constituents can then
easily learn more about the team and
check for recent updates.
This online version should also be
accompanied by a digital signature,
3.3 Charter
Every SIRT must have a charter which specifies what it is to do, and
the authority under which it will do it. The charter should include
at least the following statements:
- Mission statement
- Constituency
- Sponsor / affiliation
- Authority
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3.3.1 Mission Statement
The mission statement should focus on the team's core activities,
already stated in the definition of a SIRT. In order to be considered
a Security Incident Response Team, the team must support the reporting
of incidents and support its constituency by dealing with incidents.
The goals and purposes of a team are especially important, and require
clear, unambiguous definitions.
3.3.2 Constituency
A SIRT's constituency can be determined in many ways. For example it
could be a company's employees or its paid subscribers, or it could be
defined in terms of a technological focus, such as the users of a
particular operating system.
The definition of constituency should create a perimeter around the
group to whom the team will provide service. The policy section of
the document (see below) should explain how requests from outside the
perimeter will be handled.
If a SIRT decide, not to disclosure their constituency, they should
explain the reasoning behind this decision. For example for-fee
SIRTs will not list their clients but declare that they provide
a service to a large group of customers that are kept confidential
because of the clients' contract.
Constituencies might overlap, as when an ISP provides a SIRT, but
delivers services to customer sites which also have SIRTs. The
Authority section of the document (see below) should make such
relationships clear.
3.3.3 Sponsoring Organization / Affiliation
The sponsoring organization, which authorizes the actions of the SIRT,
should be given next. Knowing this will help the users to understand
the background and setup of the SIRT. It is vital information for
building up trust between a constituent and a SIRT.
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3.3.4 Authority
Based on the relationship between team and constituency this section
will be very different from one team to another. While an
organizational SIRT will be given its authority by the management,
a community SIRT will be supported and chosen by the community,
usually in a advisory role.
SIRTs may not have authority to intervene in the operation of all the
systems within their perimeter. They should identify the scope of
their control as distinct from the perimeter of their constituency; if
other SIRTs operate hierarchically within their perimeter, these should
be identified and addressed here.
A disclosure of a team's authority may expose it to claims of
liability. Every team should seek legal advice on these matters.
(See section 3.7 for more on liability.)
3.4 Policies
3.4.1 Types of Incidents and Level of Support
The types of incident which the team is able to address and the
level of support which the team will offer when responding to each
type of incident should be summarized here in list form. The Services
section (see below) provides opportunity for more detailed definition
and to address non-incident related topics.
The level of support might change, depending on factors like workload
or completeness of information available. Such factors should be
outlined and their impact should be explained. As a list of known
types of incidents will be incomplete with regard to possible or future
incidents, a SIRT should also give some background on the "default"
support for each reported incident.
The team should state whether it will act on information it receives
about vulnerabilities which create opportunities for future incidents.
A commitment to act on such information on behalf of its constituency is
regarded as an optional pro-active service policy rather than a core
service requirement for a SIRT.
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3.4.2 Co-operation and Interaction with other Organizations
This section should make explicit which related groups with which the
SIRT routinely interacts with. Such interactions are not related to
the Security Incident Response provided, but are used to facilitate
better cooperation on technical topics or services. By no means should
details about cooperation agreements be given out, the main objective
of this section is to give the constituency a basic understanding
what kind of interactions are established and what their purpose is.
Examples of these are listed below.
Incident Response Teams:
A SIRT will often need to interact with other SIRTs. For example
a SIRT within a large company may need to report incidents to a
national SIRT, and a national SIRT may need to report incidents
to national SIRTs in other countries to deal with all sites
involved in a large-scale attack.
Vendors:
Larger vendors have their own SIRTs, but smaller vendors may not.
In such cases a SIRT will need to work directly with a vendor to
suggest improvements or modifications, to analyse the technical
problem or to test provided solutions.
Law-enforcement agencies:
These include the police and other investigative agencies. SIRTs
and users of the template should be sensitive to local laws and
regulations, which may vary considerably in different countries.
A SIRT might advise on technical details of attacks or seek advice
on the legal implications of an incident. Local laws and
regulations may include specific reporting and confidentiality
requirements.
Press:
A SIRT may be approached by the Press for information and comment
from time to time. This is discussed in more detail immediately
below.
Other:
This might include research activities or the relation to the
sponsoring organization.
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3.4.3 Reporting and Disclosure
The default status of any and all security-related information which a
team receives will usually be 'confidential,' but rigid adherence to
this makes the team to appear as a 'black hole.' Its template should
define what information it will report or disclose, to whom, and when.
Different teams are likely to be subject to different legal restraints
requiring or limiting disclosure, especially if they work in different
jurisdictions. In addition, they may have reporting requirements
imposed by their sponsoring organization. Each team's template should
specify any such restraints, both to clarify users' expectations and to
inform other teams.
Conflicts of interest, particularly in commercial matters, may also
restrain disclosure by a team; this document does not recommend on
how such conflicts should be addressed.
'Disclosure' includes (but is maybe not limited to):
- Reporting incidents within the constituency to other teams. By
this, site related information might become public knowledge,
accessible for everybody, especially the press.
- Handling incidents occurring within the constituency, but
reported from outside it.
- Reporting observations from within the constituency indicating
suspected or confirmed incidents outside it.
- Acting on reports of incidents occurring outside the constituency.
- Passing information about vulnerabilities to vendors, to Partner
SIRTs or directly to affected sites lying within or outside the
constituency.
- Feed-back to parties reporting incidents or vulnerabilities.
- The provision of contact information relating to members of the
constituency, members of other constituencies, other SIRTs or
law-enforcement agencies.
An explicit policy concerning disclosure to the Press can be helpful,
particularly in clarifying the expectations of a SIRT's constituency.
The press policy will have to clarify the same topics as above more
specifically, as the constituency will usually be very sensitive
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towards press contacts.
The reporting and disclosure policy should make clear who will be the
recipients of a SIRT's report in each circumstance. It should also
note whether the team will expect to deal through another SIRT
or directly with a member of another constituency over matters directly
involving that member.
A team will normally collect statistics. If such information are
distributed, the template's reporting and disclosure policy should
say so, and should list methods to obtain such statistics.
3.4.4 Communication and Authentication
Methods of secure and verifiable communication should be established.
This is necessary for communication between SIRTs and between a SIRT
and its constituents. The template should include public keys or
pointers to them, including key fingerprints, together with guidelines
on how to use this information to check authenticity and how to deal
with corrupted information (for example where to report this fact to).
At the moment it is recommended that every SIRT has - if possible - as
a minimum, a PGP key available. Teams may also make other mechanisms
available (for example PEM, MOSS, S/MIME), according to its needs and
the needs of its constituents. Note however, that SIRTs and users
should be sensitive to local laws and regulations. Some countries do
not allow strong encryption or enforce specific policies on the use of
encryption technology. In addition to encrypting sensitive information
whenever possible, correspondence should include digitally signatures.
(Please note, that in most countries, the protection of authenticity
by using digital signatures is not affected by existing encryption
regulations.)
For communication via telephone or facsimile a SIRT may keep secret
authentication data for parties with whom they may deal, such as an
agreed password or phrase.
3.4.5 Point of Customer Contacts
More detailed contact information might be provided. This might
include different contacts for different services or might be a list
of online information services. If specific procedures for access to
some services exist (like addresses for mailing list requests) these
should be explained here.
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3.5 Services
Services provided by each SIRT can be differentiated by whether they
relate to the main task, which is incident response, or are provided
in addition (optional in regard to the definition of a SIRT).
Incident response, which usually includes:
- Verification Help with the verification of
incidents, as well as their scope.
- Technical Assistance This may include analysis of
compromised systems.
- Eradication Elimination of the effects of a
security incident.
- Recovery Aid in restoring affected systems
and services to their status before
the security incident.
- Notification of other involved parties
Additional or optional services, which might include:
- Information provision This might include an archive of
known vulnerabilities, patches or
resolutions of past problems.
- Security Tools
- Education and training
- Product evaluation
- Site security auditing and consulting
3.6 Incident Reporting Forms
The use of reporting forms makes it simplier for both sides, users and
teams, to deal with incidents. The constituent may prepare answers to
various important questions before he or she actually contacts the team
and therefore come well prepared. The team gets all the necessary
information at once with the first report and can proceed efficiently.
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Depending on the objectives and services of a single SIRT, multiple
forms may be used, for example a reporting form for a new vulnerability
will be very different for the form used for reporting incidents.
It is most efficient to provide forms through the online information
services of the team. The exact pointers to them should be given in
the document, together with statements about appropriate use and
guidelines, for when and how to use the forms. If separate e-mail
addresses are supported for form based reporting, they should be
listed here again.
One example for such form is the Incident Reporting Form provided by
the CERT Coordination Center:
- ftp://info.cert.org/incident_reporting_form
3.7 Disclaimers
Although the document does not constitute a contract, liability might
conceivably result from its descriptions of services and purposes. The
inclusion of a disclaimer at the end of the template is therefore
recommended and should warn the user about possible limitations.
It should be noted that some forms of reporting or disclosure relating
to specific incidents or vulnerabilities can also imply liability, and
SIRTs should consider the inclusion of disclaimers in such material.
In situations where the original version of a document must be
translated into another language, the translation should carry a
disclaimer and a pointer to the original. For example:
Although we tried to carefully translate the original
document from German into English, we can not be certain
that both documents express the same thoughts in the same
level of detail and correctness. In all cases, where there
is a difference between both versions, the German version
is the binding version.
The use of and protection by disclaimers is effected by local laws and
regulations. Therefore each SIRT should be sensitive and if in doubt
should check the disclaimer with a lawyer.
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4 Appendix A: Glossary of Terms
This glossary defines terms used in describing security incidents and
Security Incident Response Teams. Only a limited list is included.
For more definitions please refer to other sources, for example to the
[RFC 1983].
Constituency:
Implicit in the purpose of a Security Incident Response Team is
the existence of a constituency. This is the group of users,
sites, networks or organizations served by the team. The team
must be recognized by its constituency to be effective.
Security Incident:
For the purpose of this document this term is synonym to Computer
Security Incident: Any adverse event which compromises some aspect
of computer or network security.
The definition of an incident may vary between organizations, but
at least the following categories are generally applicable:
- Loss of confidentiality of information.
- Compromise of integrity of information.
- Denial of service.
- Misuse of service, systems or information.
- Damage of systems.
These are very general categories. For instance the replacement
of a system utility program by a Trojan Horse is an example of
'compromise of integrity,' and a successful password attack is an
example of 'loss of confidentiality.' Attacks, even if they
failed because of proper protection, might be regarded as an
Incident.
Within the definition of an incident the word 'compromised' is
used. Sometimes an administrator may only 'suspect' an incident.
During the response it must be established whether or not an
incident really occurred.
Security Incident Response Team:
Based on two of the definitions given above, a SIRT is a team
that coordinates and supports the response to security incidents
that involve sites within a defined constituency.
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Expectations for Security Incident Response 26 March 97
In order to be considered a SIRT, a team must:
- Provide a (secure) channel for receiving reports about
suspected incidents.
- Provide assistance to members of its constituency in
handling these incidents.
- Disseminate incident-related information to its
constituency and to other involved parties.
Note that we are not referring here to police or other law
enforcement bodies which may investigate computer-related crime.
SIRT members, indeed, should not need to have any powers beyond
those of ordinary citizens.
Vendor:
A 'vendor' is any entity that produces networking or computing
technology, and is responsible for the technical content of that
technology. Examples of 'technology' include hardware (desktop
computers, routers, switches, etc.), and software (operating
systems, mail forwarding systems, etc.).
Note that the supplier of a technology is not necessarily the
'vendor' of that technology. As an example, an Internet Services
Provider (ISP) might supply routers to each of its customers, but
the 'vendor' is the manufacturer, being the entity responsible for
the technical content of the router, rather than the ISP.
Vulnerability:
A 'vulnerability' is a characteristic of a piece of technology
which can be exploited to perpetrate a security incident. For
example, if a program unintentionally allowed ordinary users to
execute arbitrary operating system commands in privileged mode,
this "feature" would be a vulnerability.
5 Appendix B: Related Material
Important issues in responding to security incidents on a site level
are contained in [RFC 1244], the Site Security Handbook, produced by
the Site Security Handbook Working Group (SSH). This document will
be updated by the SSH working group and will give recommendations for
local policies and procedures, mainly related to the avoidance of
security incidents.
Other documents of interest for the discussion of SIRTs and their
tasks are available by anonymous FTP. A collection can be found on:
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Expectations for Security Incident Response 26 March 97
- ftp://ftp.cert.dfn.de/pub/docs/csir/
Please refer to file 01-README for further information about
the content of this directory.
Some especially interesting documents in relation to this document are
as follows:
- ftp://ftp.nic.surfnet.nl/surfnet/net-security/cert-nl/docs/
reports/R-92-01
This report contains the Operational Framework of CERT-NL, the
SIRT of SURFnet (network provider in the Netherlands).
- For readers interested in the operation of FIRST (Forum of
Incident Response and Security Teams) more information is
collected in Appendix C.
- http://hightop.nrl.navy.mil/news/incident.html
This document leads to the NRL Incident Response Manual.
- http://www.cert.dfn.de/eng/team/kpk/certbib.html
This document contains an annotated bibliography of available
material, documents and files about the operation of SIRTs
with links to many of the referenced.
- ftp://info.cert.org/incident_reporting_form
This Incident Reporting Form is provided by the CERT
Coordination Center to gather incident information and to avoid
additional delays by requesting the sites for more detailed
information.
- http://www.cert.org/cert.faqintro.html
A collection of frequently asked questions from the CERT
Coordination Center.
6 Appendix C: Known Security Incident Response Teams
Today, there are many different SIRTs but no single source list every
team. Most of the major and long established teams (the first SIRT was
founded in 1988) are nowadays member of FIRST, the worldwide Forum of
Incident Response and Security Teams. Actually more than 55 teams are
members (1 in Australia, 13 in Europe, all others from America).
Information about FIRST can be found:
- http://www.first.org/
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The actual list of members is available also, with the relevant contact
information and some additional information provided by the single
teams:
- http://www.first.org/team-info/
For SIRTs which want to become members of this forum (please note, that
a team needs a sponsor - a team already full member of FIRST - to be
introduced), the following files contain more information:
- http://www.first.org/about/op_frame.html
The Operational Framework of FIRST.
- http://www.first.org/docs/newmem.html
Guidelines for teams which want to become member of FIRST.
Many of the European teams, regardless if they are members of FIRST or
not, are listed by countries on a page maintained by the German SIRT:
- http://www.cert.dfn.de/eng/csir/europe/certs.html
To learn about existing teams and maybe more suitable teams for one's
need it is always a good approach, to ask either existing teams or an
Internet Service Provider for the "right" contact.
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7 Appendix D: Outline for SIRT Template
This outline summarizes the issues addressed in this document in a logical
structure suitable to communicate the policies and procedures for the
interaction with SIRTs easily to the team's constituency. A 'filled-in'
example of this template is given as Appendix E.
1. Contact Information
1.1 Name of the Team
1.2 Address
1.3 Time Zone
1.4 Telephone Number
1.5 Facsimile Number
1.6 Other Telecommunication
1.7 Electronic Mail Address
1.8 Public Keys and Encryption Information
1.9 Team Members
1.10 Other Information
2. Document Updates
2.1 Date of Last Update
2.2 Distribution List for Notifications
2.3 Locations where this Document May Be Found
3. Charter
3.1 Mission Statement
3.2 Constituency
3.3 Sponsors and/or Affiliation
3.4 Authority
4. Policies
4.1 Types of Incidents and Level of Support
4.2 Cooperation and Interaction with Other Entities
4.3 Disclosure of Information
4.4 Communication and Authentication
4.5 Points of Customer Contacts
5. Services
5.1 Incident Response
5.2 Proactive Activities
6. Incident Reporting Forms
7. Disclaimers
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8 Appendix E: Example - 'filled-in' Template for a SIRT
Below is an example, a filled-in template for a SIRT called XYZ
to avoid any confusion with existing teams. By no means does this
example imply, that a new founded SIRT should reuse this text.
It is for example purposes only.
SIRT Template for XYZ-SIRT
--------------------------
Note: no digital signature is currently available for this SIRT
Template. We'll put one up as soon as the technology is adopted
by XYZ Enterprises.
1. Contact Information
1.1 Name of the Team
"XYZ-SIRT": the XYZ Computer Emergency Response Team.
1.2 Address
XYZ SIRT
XYZ Enterprises
Private Bag 12-345
MyTown
MyCountry
1.3 Time Zone
MyCountry/Eastern (GMT-0500, and GMT-0400 from April to October)
1.4 Telephone Number
+1 234 567 7890 (ask for the XYZ-SIRT)
1.5 Facsimile Number
+1 234 567 7654 (this is *not* a secure fax)
1.6 Other Telecommunication
None available.
1.7 Electronic Mail Address
<xyz-sirt@sirt.xyz.org>
1.8 Public Keys and Other Encryption Information
Encryption is not currently available, but we plan to install
PGP as soon as possible. Our PGP public key will appear here
as soon as it is available.
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1.9 Team Members
Jane Doe of Computing Services is the XYZ-SIRT
coordinator. Other team members will be listed here once
their participation is confirmed.
2. Document Updates
2.1 Date of Last Update
Please see the bottom of this Web page for this information.
2.2 Distribution List for Notifications
Notifications of updates are submitted to our mailing list
<xyz-sirt-info@sirt.xyz.org>. (Subscription request should
go to <xyz-sirt-info-request@sirt.xyz.org>.)
2.3 Locations where this Document May Be Found
This template is available from the XYZ SIRT WWW
site; its URL is
http://www.sirt.xyz.org/op_frame.html
The template will be signed with the XYZ-SIRT's PGP
key.
3. Charter
3.1 Mission Statement
The purpose of the XYZ-SIRT is, first, to assist members of
XYZ community in implementing proactive measures to reduce
the risks of computer security incidents, and second, to
assist XYZ community in responding to such incidents when
they occur.
3.2 Constituency
The XYZ-SIRT's constituency is the XYZ SIRT community,
as defined in the context of the "XYZ Policy on Computing
Facilities".
3.3 Sponsors and/or Affiliation
None.
3.4 Authority
The XYZ-SIRT operates under the auspices of, and with
authority delegated by, the Department of Computing Services
of XYZ Enterprises. The Department in turn receives its
authority from the formal ruling bodies of XYZ, as
set out in the "Policy on Computing Facilities". The XYZ-SIRT
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Expectations for Security Incident Response 26 March 97
has no direct authority over systems at XYZ Enterprises
at large. However, it benefits from the direct authority of
Computing Services with respect to systems managed by this
Department. Also, because Computing Services manages the
XYZ Enterprises Network, and is responsible for connectivity
to it, the Department has indirect authority over systems
in other departments, inasmuch as the Department can order
such systems to be disconnected from the network should
circumstances warrant it.
The XYZ-SIRT expects to work cooperatively with system
administrators and users at XYZ, and, insofar as
possible, to avoid authoritarian relationships. However,
should circumstances warrant it, the XYZ-SIRT will appeal to
Computing Services to exert its authority, direct or indirect,
as necessary.
4. Policies
4.1 Types of Incidents and Level of Support
The XYZ-SIRT is authorized to address all types of computer
security incidents which occur, or risk occurring, at
XYZ Enterprises.
The level of support given by XYZ-SIRT will vary depending on
the type and severity of the incident or issue, the type of
consituent, the size of the user community affected, and the
XYZ-SIRT's resources at the time.
No direct support will be given to end users; they are
expected to contact their system administrator, network
administrator, or department head for assistance. The
XYZ-SIRT will support the latter people.
While the XYZ-SIRT understands that there exists great
variation in the level of system administrator expertise at
XYZ, and while the XYZ-SIRT will endeavor to present
information and assistance at a level appropriate to
each person, the XYZ-SIRT cannot train system administrators,
and it cannot perform system maintenance on their behalf.
In most cases, the XYZ-SIRT will provide pointers to the
information needed to implement appropriate measures.
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4.2 Cooperation and Interaction with Other Entities
- Other sites:
The XYZ-SIRT will cooperate with other SIRTs (security
incident response teams) and with system administrators at
other sites, to the extent that their bona fide can be
verified. Should provincial or national SIRTs be
constituted, XYZ-SIRT will explore the possibility of peer
relationships with them. The possibility of peer
relationships with close neighbors will also be explored;
unofficial cooperative climates already exist between XYZ
and several nearby universities and large corporations.
While there are no legal requirements that XYZ-SIRT provide
any information to any body outside XYZ (aside from
law enforcement agencies), XYZ-SIRT will provide such
information when the good of the community justifies it.
However, unless identifying information is needed to track
an incident in progress, such information will be stripped
from the report (unless the affected department gives its
permission that the real information be used).
- Vendors:
The XYZ-SIRT wishes to encourage vendors of all kinds of
networking and computer equipment, software, and services
to improve the security of their products. In aid of
this, a vulnerability discovered in such a product will be
reported to its vendor, along with all technical details
needed to identify and fix the problem. Identifying
details will not be given to the vendor without the
permission of the affected parties.
- Law enforcement:
XYZ has its own Security Department. ( I NEED TO LOOK UP
THE RELATIONSHIP BETWEEN COMPUTING SERVICES, XYZ
SECURITY, AND OUTSIDE POLICE FORCES. ) Informal working
relationships already exist between some system
administrators at XYZ and the local police; interest
has been expressed by all parties in formalizing these
relationships. Any progress
made in that area will be reflected in this section.
In the meantime, authorized and unauthorized users of the
XYZ Computing Facilities should be aware that the
XYZ-SIRT will cooperate fully with law enforcement
agencies in detecting, reporting, documenting, and
prosecuting violations of the law; users concerned about
confidentiality are referred to the XYZ "Policy on
Computing Facilities".
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Expectations for Security Incident Response 26 March 97
- The Press:
The XYZ-SIRT will not interact directly with the Press.
If necessary, information will be provided to the
XYZ Public Relations Department, and to the
Customer Relations group of the Computing Services
Department. All queries will be referred to these two
bodies.
- The XYZ SIRT community:
Details of incidents may be released to Computing Services
management, XYZ management, or the Computer
Resources Committee; these bodies will be charged with
maintaining the confidentiality of the information. General
report of incidents, summaries of multiple incidents, and
statistics may be made available to the general XYZ
community, with identifying information stripped (except
where permission has been obtained from the affected
parties). There is no obligation on the part of the
XYZ-SIRT to report incidents to the community, though it
may choose to do so; in particular, it is likely that the
XYZ-SIRT will inform all affected parties of the ways in
which they were affected.
- The public at large:
In general, no particular efforts will be made to
communicate with the public at large, though the XYZ-SIRT
recognizes that, for all intents and purposes, information
made available to the XYZ community is in effect
made available to the community at large, and will tailor
the information in consequence.
- The computer security community:
While members of XYZ-SIRT may participate in discussions
within the computer security community, such as newsgroups,
mailing lists (including the full-disclosure list
"bugtraq"), and conferences, they will treat such forums
as though they were the public at large. While technical
issues (including vulnerabilities) may be discussed to any
level of detail, any examples taken from XYZ-SIRT
experience will be disguised to avoid identifying the
affected parties.
In the paragraphs above, the "affected parties" refers to the
legitimate owners, operators, and users of the relevant
computing facilities. It does not refer to unauthorized
users, including otherwise authorized users making
unauthorized usage of a facility; such intruders may have no
expectation of confidentiality from the XYZ-SIRT. They may or
may not have legal rights to confidentiality; such rights will
of course be respected where they exist.
4.3 Disclosure of Information
The following types of information will be stored and handled
by XYZ-SIRT:
- Contact info for constituents.
- Technical info about a vulnerability.
- Technical info about XYZ facilities.
- Information about incidents:
- Statistical summaries
- Admission of incident of certain type
- Admission of root compromise
- Admission of packet sniffing attack
- Admission that user accounts were compromised
- Description of incident
- Identity of affected systems
- Identity of affected people
- Identity of perpetrator
Recipients of information are - depending on the need to
know - are as follows:
- XYZ management
- Computing Services management
- Affected sysadmin at XYZ
- Affected sysadmin (or SIRT) at another site
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- Affected user(s) at XYZ
- All sysadmins potentially concerned (potentially
vulnerable) at XYZ
- All sysadmins at XYZ
- All users potentially concerned at XYZ
(information will leak to general public)
- All users at XYZ (ditto)
- Computer security community
- Peer sysadmins and SIRTs
- Vendors
- Law enforcement
4.4 Communication and Authentication
In view of the types of information that the XYZ-SIRT will
likely be dealing with, telephones will be considered
sufficiently secure to be used even unencrypted. Unencrypted
e-mail will not be considered particularly secure, but will be
sufficient for the transmission of low-sensitivity data. If
it is necessary to send highly sensitive data by e-mail, PGP
will be used. Network file transfers will be considered to
be similar to e-mail for these purposes.
Where it is necessary to establish trust, for example before
relying on information given to the XYZ-SIRT, or before
disclosing confidential information, the identity and bona
fide of the other party will be ascertained to a reasonable
degree of trust. Within XYZ, and with known
neighbor sites, referrals from known trusted people will
suffice to identify someone. Otherwise, appropriate methods
will be used, such as a search of FIRST members, the use of
WHOIS and other Internet registration information, etc, along
with telephone call-back or e-mail mail-back to ensure that
the party is not an impostor. Incoming e-mail whose data must
be trusted will be checked with the originator personally, or
by means of digital signatures.
4.5 Points of Customer Contact
The preferred method for contacting the XYZ-SIRT will be
e-mail. If this is not possible, or not advisable for
security reasons, the XYZ-SIRT can be reached by telephone
during regular office hours.
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5. Services
5.1 Incident Response
XYZ-SIRT will help users and administrators to handle the
technical and organizational aspects of incidents. By that,
it will provide and facilitate:
- to understand the extend of the incident
- ...
5.2 Proactive Activities
The XYZ-SIRT will coordinate and maintain the following
services to the extent possible depending on its resources:
- Information services
- List of departmental security contacts, administrative
and technical.
- Mailing lists to inform security contacts of new
information relevant to their computing environments.
- Repository of vendor-provided and other security-related
patches for various operating systems.
- Repository of security tools for use by sysadmins.
- "Clipping" service for various existing resources, such
as major mailing lists and newsgroups.
- Auditing services
- Central file integrity checking service for Unix
machines.
- Security level assignments; machines at XYZ
will be audited and assigned a security level.
- Archiving services
- Records of security incidents handled.
6. Incident Reporting Forms
There are no own forms developed yet for reporting incidents
to XYZ-SIRT. If possible, please make us of the Incident
Reporting Form of the CERT Coordination Center (Pittsburgh, PA).
The actual version is available from:
ftp://info.cert.org/incident_reporting_form
7. Disclaimers
While every precaution will be taken in the preparation of
information, notifications and alerts, XYZ-SIRT assumes no
responsibility for errors or omissions, or for damages
resulting from the use of the information contained within.
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9 References
[RFC 1244] P. Holbrooks, J. Reynolds / Site Security Handbook. - July 23,
1991. - 101 pages. - FYI 8.
[RFC 1983] G. Malkin / Internet Users' Glossary. - August 16, 1996. -
62 pages. - FYI 18.
10 Security Considerations
This document discusses issues of the operation of Security Incident
Response Teams, and the teams interactions with their constituency.
It is therefore not directly concerned with the security of protocols,
applications or network systems themselves. It is not even concerned
about the response and reaction to security incidents.
Nonetheless, it is vital that SIRTs establish secure communication
channels with other teams, and with members of their constituency.
They must also secure their own systems and infrastructure, to protect
the interests of their constituency and to maintain the confidentiality
of the identity of victims and reporters of security incidents.
11 Authors' Addresses
Nevil Brownlee
ITSS Technology Development
The University of Auckland
Phone: +64 9 373 7599 x8941
E-mail: n.brownlee@auckland.ac.nz
Erik Guttman
Sun Microsystems, Inc.
Gaisbergstr. 6
69115 Heidelberg Germany
Phone: +49 6221 601649
E-Mail: eguttman@eng.sun.com
This document expires September 26, 1997.
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