Enhancing ICMP Error Message Authentication Using Challenge-Confirm Mechanism
draft-xu-intarea-challenge-icmpv4-02
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| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Authors | Ke Xu , Xuewei Feng , Yuxiang Yang , Li Qi | ||
| Last updated | 2025-11-02 | ||
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| Intended RFC status | (None) | ||
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draft-xu-intarea-challenge-icmpv4-02
Internet Area Working Group K. Xu
Internet-Draft Tsinghua University & Zhongguancun Laboratory
Intended status: Informational X. Feng
Expires: 6 May 2026 Y. Yang
Tsinghua University
Q. Li
Tsinghua University & Zhongguancun Laboratory
2 November 2025
Enhancing ICMP Error Message Authentication Using Challenge-Confirm
Mechanism
draft-xu-intarea-challenge-icmpv4-02
Abstract
The Internet Control Message Protocol (ICMP) is essential for network
diagnostics but is vulnerable to off-path spoofing attacks,
especially when error messages relate to stateless transport
protocols like UDP. An attacker can forge these messages to degrade
performance or enable Man-in-the-Middle attacks.
This document proposes a robust, stateless challenge-response
mechanism to authenticate ICMP error messages. Traditional stateful
challenge mechanisms are vulnerable to state-exhaustion Denial-of-
Service (DoS) attacks. To avoid this, the proposed solution is
inspired by TCP SYN-Cookies, eliminating the need to store per-
challenge state by using cryptographic computation. It limits state
management to minimal flags on existing sockets or a bounded
probabilistic data structure. This approach effectively
authenticates ICMP error messages while inherently resisting both
off-path spoofing and state-exhaustion DoS attacks, thus improving
the robustness of ICMP.
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
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Internet-Drafts are draft documents valid for a maximum of six months
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material or to cite them other than as "work in progress."
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This Internet-Draft will expire on 6 May 2026.
Copyright Notice
Copyright (c) 2025 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 (https://trustee.ietf.org/
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Please review these documents carefully, as they describe your rights
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provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Problem Statement . . . . . . . . . . . . . . . . . . . . . . 4
3.1. Source-Based Blocking Ineffectiveness . . . . . . . . . . 4
3.2. Authentication Evasion based on Embedded Packet State . . 4
3.2.1. Stateful Embedded Packets (e.g., TCP) . . . . . . . . 4
3.2.2. Stateless Embedded Packets (e.g., UDP, ICMP) . . . . 4
4. Stateless Challenge-Confirm Mechanism . . . . . . . . . . . . 5
4.1. Core Principle: Eliminating State with Cryptographic
Computation . . . . . . . . . . . . . . . . . . . . . . . 5
4.2. Challenge-Confirm Procedure . . . . . . . . . . . . . . . 5
4.3. Protocol-Specific State Management . . . . . . . . . . . 7
4.4. Challenge-Confirm Option . . . . . . . . . . . . . . . . 8
5. Exception Handling and Edge Cases . . . . . . . . . . . . . . 9
5.1. Packet Loss . . . . . . . . . . . . . . . . . . . . . . . 9
5.2. Multi-Path Routing Scenarios . . . . . . . . . . . . . . 10
6. Security Considerations . . . . . . . . . . . . . . . . . . . 10
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 12
8.1. Normative References . . . . . . . . . . . . . . . . . . 12
8.2. Informative References . . . . . . . . . . . . . . . . . 12
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 13
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 13
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1. Introduction
The Internet Control Message Protocol (ICMP) [RFC792] is an integral
part of network operations, providing essential feedback on
transmission issues. However, the legitimate verification of ICMP
error messages is inherently vulnerable by design. To enable senders
to correlate error reports with the original packets for effective
network diagnostics, ICMP error messages, as specified in [RFC792],
MUST include the header information and a portion of the payload of
the original message that triggered the error. When the original
message originates from stateless protocols like UDP or ICMP, the
embedded original message header lacks contextual information (e.g.,
sequence numbers, acknowledgement numbers, and ports in stateful
protocols like TCP). This makes it difficult for the receiver to
effectively verify the legitimacy of the error messages.
Consequently, attackers can forge ICMP error messages embedded with
stateless protocol payloads to bypass the legitimate verification of
the receiver, tricking the receiver into erroneously accepting and
responding to the message, which can lead to malicious activities.
For example, off-path attackers can forge ICMP "Fragmentation Needed"
messages to degrade throughput and harm latency-sensitive
applications. This can also induce TCP segment fragmentation
[NDSS2022MTU] and enable IP ID-based TCP session hijacking
[CCS2020IPID]. Moreover, forged ICMP Redirect messages embedded with
stateless protocol data can be used to trick victims into modifying
their routing, facilitating off-path traffic interception,
modification, and credential theft [USENIXSECURITY2023ICMP],
[SP2023MITM]. These diverse attack vectors starkly underscore the
critical and urgent necessity for robust authentication mechanisms in
ICMP for error message processing.
This document proposes a stateless challenge-confirm mechanism that
authenticates these ICMP error messages. The mechanism is designed
to prove that the source of an error is on the path of the associated
data flow, thwarting off-path attackers without introducing new
Denial-of-Service vulnerabilities.
2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119]. TCP
terminology should be interpreted as described in [RFC9293].
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3. Problem Statement
Current ICMP specifications have inherent limitations that allow off-
path attackers to forge ICMP error messages, undermining network
security and reliability. The primary issues are:
3.1. Source-Based Blocking Ineffectiveness
Certain ICMP error messages, such as "Fragmentation Needed" messages,
can originate from any intermediate router along the packet's path.
This ubiquity makes source-based blocking ineffective, as legitimate
messages can come from multiple sources.
3.2. Authentication Evasion based on Embedded Packet State
Although [RFC792] and [RFC1122] stipulate that error messages should
include as much of the original (offending) packet as possible, the
inherent characteristics of the embedded packet protocol directly
influence the difficulty of authenticating ICMP error messages and
their overall security strength.
3.2.1. Stateful Embedded Packets (e.g., TCP)
When attackers embed stateful protocol packets, such as TCP segments,
in forged ICMP error messages, receivers can theoretically utilize
the inherent state information of the TCP protocol for a certain
degree of verification. The TCP protocol establishes and maintains
state between communicating parties through sequence numbers,
acknowledgment numbers, and ports. These connection-based TCP state
information are difficult for attackers to accurately guess.
Receivers can attempt to verify whether these connection-specific
details in the embedded TCP header match their maintained TCP
connection state, thereby judging the authenticity of the ICMP error
message.
3.2.2. Stateless Embedded Packets (e.g., UDP, ICMP)
In contrast to stateful TCP, when attackers embed stateless protocol
packets, such as UDP or ICMP messages, in forged ICMP error messages,
receivers lose the ability to perform effective state verification.
UDP and ICMP protocols are inherently designed as stateless
protocols. The UDP or ICMP messages embedded in ICMP error messages
contain almost no state information that can be used for context
verification. In addition to performing some basic protocol format
checks, receivers have virtually no way to determine the authenticity
of ICMP error messages based on the embedded stateless packet header.
This lack of state verification greatly reduces the authentication
strength of ICMP error messages, making it easier for attackers to
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implement authentication evasion and use forged error messages for
malicious attacks.
4. Stateless Challenge-Confirm Mechanism
A simple stateful challenge-response mechanism, where a host stores a
nonce while waiting for a confirmation, would introduce a critical
state-exhaustion Denial-of-Service (DoS) vulnerability. An attacker
could flood a target with forged error messages, forcing it to
allocate state for each one. To solve this, the mechanism proposed
here is stateless and inspired by TCP SYN-Cookies [RFC4987], where
state is not stored but is instead encoded cryptographically and
later re-computed for validation.
4.1. Core Principle: Eliminating State with Cryptographic Computation
Instead of generating and storing a random nonce, the host computes a
deterministic nonce on demand. This nonce is a cryptographic hash of
information that defines the flow, combined with a secret key known
only to the host.
Challenge Nonce = F(secret_key, src_IP, dest_IP, [other_flow_info])
* secret_key: A high-entropy secret value held by the host's
operating system. This key MUST be rotated periodically (e.g.,
every few minutes) to limit the impact of any potential key
compromise and to mitigate replay attacks.
* F: A keyed-hash function, such as HMAC-SHA256, truncated to the
size of the nonce field.
With this approach, a nonce can be generated when needed (for an
outgoing challenge) and verified later (on a returning confirmation)
by simply re-computing it. There is no need to store it in a cache.
4.2. Challenge-Confirm Procedure
The stateless process is as follows:
* Receive and Validate Error: Host A receives an ICMP error message.
It first validates the embedded header's 4-tuple against its list
of active sockets/connections. If no matching socket exists, the
message is silently discarded. No state is created.
* Mark Flow for Challenge: If a matching socket is found, Host A
does not create new state. Instead, it sets a simple flag on the
existing socket control block, marking it as "requires challenge".
The initial ICMP error is then discarded.
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* Issue Computed Challenge: The next time the application sends a
packet on this marked socket, the networking stack intercepts it.
It computes the challenge nonce using the secret key and the
packet's flow information. This nonce is placed in a Challenge-
Confirm IP Option, and the packet is sent.
* Receive and Verify Confirmation: If a legitimate on-path node
returns a new ICMP error, it will contain the challenge packet.
Host A receives this new error, extracts the embedded nonce, and
recomputes the expected nonce using the same secret key and flow
information.
* Process or Discard: If the received nonce matches the re-computed
one, the error is authentic, and Host A can act on it. If it does
not match, the message is a forgery or is stale, and it is
discarded.
This flow achieves the anti-spoofing goal without creating state for
unverified messages, thus defeating potential DoS attacks. Figure 1
illustrates the complete interaction.
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Host A On-Path Router R
| |
|--------[ Original UDP Packet ]---------->|
| X (Error, e.g., MTU exceeded)
|<--[ 1. ICMP Error (Original) ]-----------|
| |
| [Internal Action on Host A:] |
| - Validate 4-tuple -> OK |
| - Mark socket for challenge |
| - Discard original error msg |
| (No per-challenge state is stored) |
| |
|--------[ 2. Next UDP Packet + ]--------->|
| [ Challenge Option (Nonce N) ] |
| (Nonce N computed on-the-fly) |
| |
| X (Same error condition)
|<--[ 3. New ICMP Error (contains N) ]-----|
| |
| [Internal Action on Host A:] |
| - Extract received Nonce N |
| - Re-compute expected Nonce N' |
| - IF (N == N') THEN: |
| Process error (SUCCESS) |
| ELSE: |
| Discard message (FAILURE) |
| |
Figure 1: Challenge-Confirm Mechanism
4.3. Protocol-Specific State Management
The mechanism for "marking a flow" is lightweight and transport-
specific.
* *UDP*: Upon receiving a validatable ICMP error, the host sets a
flag on the corresponding UDP socket's control block.
* *TCP*: While TCP has its own protections, this mechanism can
supplement it. A flag can be set on the TCB.
* *ICMP*: For connectionless protocols like ICMP Echo, which lack a
socket state, a probabilistic, fixed-size data structure like a
Sketch or Bloom Filter SHOULD be used.
- On Error Reception: The host hashes a flow identifier (e.g.,
source IP, destination IP, ICMP Identifier) and increments the
corresponding counter(s) in the sketch.
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- On Packet Transmission: When sending a new ICMP packet, the
host queries the sketch. If the query indicates this flow has
likely received a recent error, it attaches the computed
challenge. This probabilistic approach ensures that state
remains bounded, preventing DoS attacks against ICMP-based
applications.
4.4. Challenge-Confirm Option
To support the Challenge-Confirm mechanism, this document defines a
new Challenge-Confirm IP Option. The challenge packet for a received
ICMP error message containing a stateless protocol payload includes
this option in the IP header (as shown in Figure 2). Similarly, the
ICMP error message triggered in response to this challenge packet
should also include the same option in the header of the embedded IP
challenge packet (as shown in Figure 3).
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Version| IHL |Type of Service| Total Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Identification |Flags| Fragment Offset |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Time to Live | Protocol | Header Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Source Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Destination Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Option Type | Opt Data Len | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| Challenge Nonce (128 bits) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| Stateless Protocol Data (UDP/ICMP packet) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: The IPv4 Challenge Packet with Challenge-Confirm Option
The fields in the Challenge-Confirm Option are defined as follows:
* *Option Type*: 8-bit identifier for the challenge-confirm option.
The final value requires IANA assignment.
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* *Opt Data Len*: 8-bit unsigned integer specifying the length of
the option data field in bytes.
* *Reserved*: 16-bit field reserved for future use. MUST be set to
zero on transmission and ignored on reception.
* *Challenge Nonce*: 128-bit number computed as described in
Section 4.1.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| unused |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Version | IHL | Type of Service | Total Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Identification | Flags | Fragment Offset |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Time to Live | Protocol | Header Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Source Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Destination Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Option Type | Opt Data Len | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| Challenge Nonce (128 bits) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Stateless Protocol Data (UDP/ICMP packet) |
| (Variable Length) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: New ICMP Error Responding to the Challenge Packet
5. Exception Handling and Edge Cases
5.1. Packet Loss
The proposed mechanism is inherently resilient to packet loss due to
its stateless design. It does not maintain timers or retransmission
states for the challenge-confirm exchange itself. The requires
challenge flag is cleared as soon as the challenge packet is
transmitted, meaning the host does not enter a state of "waiting for
a confirmation".
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Whether the outgoing challenge packet or the returning ICMP
confirmation is lost in transit, the outcome is the same: the host
that issued the challenge does not receive a confirmation and takes
no special action. The exchange silently fails.
Recovery is not driven by a timer, but by the persistence of the
underlying network issue. If the condition that caused the initial
ICMP error persists, a subsequent data packet from the application
will likely trigger a new, initial ICMP error, naturally restarting
the challenge process. This "fire-and-forget" approach avoids adding
stateful complexity for the challenge itself.
5.2. Multi-Path Routing Scenarios
The mechanism's performance, but not its security, can be affected in
networks that employ per-packet load balancing across multiple paths.
Consider a scenario where a flow's packets alternate between a "bad"
path that triggers an ICMP error and a "good" path that does not.
A recurring cycle could emerge: 1. A data packet is routed to the
"bad" path, triggering an initial ICMP error and causing the host to
set the requires challenge flag. 2. The next packet (now a challenge
packet) is routed to the "good" path and reaches its destination
successfully. No ICMP confirmation is returned. 3. The host, having
sent its challenge, clears the flag. The next data packet is a
normal packet, which is again routed to the "bad" path, restarting
the cycle.
This cycle does not compromise the security of the mechanism. The
host never acts on an unvalidated ICMP error, so spoofing attacks
remain ineffective. However, it creates a performance degradation.
In this specific scenario, the effective throughput for the flow
could be halved. This is a performance cost in certain network
topologies, not a security vulnerability.
6. Security Considerations
The proposed enhancements aim to bolster ICMP security by addressing
specific vulnerabilities related to message authentication. Key
security aspects include:
* *Authentication Strength*: The security of the authentication
depends on the unguessability of the computed nonce, which is
guaranteed by the use of a strong keyed-hash function and a secret
key with sufficient entropy [RFC4086].
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* *Denial of Service (DoS) Resistance*: This is the principal
security advantage over stateful designs. The mechanism is
resilient to state-exhaustion attacks because:
1. It creates no state for ICMP errors that do not correspond to
an existing, active transport-layer socket.
2. For valid flows, the state added is minimal (a flag) or
probabilistically bounded (a sketch), preventing uncontrolled
resource consumption.
* *Replay Attack Mitigation*: The periodic rotation of the
secret_key provides the primary defense against replay attacks. A
captured nonce-confirmation pair will become invalid after the key
is changed. The rotation interval presents a trade-off between
security and the maximum legitimate round-trip time for a
challenge-confirm exchange.
* *Reflection and Amplification Attacks*: The mechanism is designed
to be immune to reflection and amplification attacks. An attacker
cannot use this protocol to turn a victim into a traffic
amplifier. The critical design choice preventing this is that the
receipt of an initial, unverified ICMP error message does NOT
trigger the immediate transmission of a new packet. Instead, the
host's response is limited to two low-cost internal actions:
silently discarding the incoming message and setting a lightweight
flag on an existing socket's control block. The challenge packet
itself is not a new, separately generated packet; it is the _next
application packet_ for that flow, modified on-the-fly to include
the Challenge-Confirm option. Therefore, an attacker sending a
flood of forged ICMP messages cannot compel the target to generate
any network traffic beyond what its applications would have sent
anyway. The victim does not become a reflector.
* *Backward Compatibility*: The mechanism is fully backward-
compatible. Hosts not implementing this specification will ignore
the IP Option as per standard IP header processing rules
[RFC1122]. Intermediate routers are unaffected. Only end hosts
wishing to enhance their security need to implement the changes.
7. IANA Considerations
The Challenge-Confirm Option Type should be assigned in IANA's "IP
Option Numbers" registry [RFC2780].
This draft requests the following IP Option Type assignments from the
IP Option Numbers registry in the Internet Protocol (IP) Parameters
registry group (https://www.iana.org/assignments/ip-parameters).
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+======+=======+========+=======+======================+============+
| Copy | Class | Number | Value | Name | Reference |
+======+=======+========+=======+======================+============+
| TBD | TBD | TBD | TBD | Challenge-Confirm | This draft |
+------+-------+--------+-------+----------------------+------------+
8. References
8.1. Normative References
[RFC1122] Braden, R., Ed., "Requirements for Internet Hosts -
Communication Layers", STD 3, RFC 1122,
DOI 10.17487/RFC1122, October 1989,
<https://www.rfc-editor.org/rfc/rfc1122>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/rfc/rfc2119>.
[RFC2780] Bradner, S. and V. Paxson, "IANA Allocation Guidelines For
Values In the Internet Protocol and Related Headers",
BCP 37, RFC 2780, DOI 10.17487/RFC2780, March 2000,
<https://www.rfc-editor.org/rfc/rfc2780>.
[RFC4086] Eastlake 3rd, D., Schiller, J., and S. Crocker,
"Randomness Requirements for Security", BCP 106, RFC 4086,
DOI 10.17487/RFC4086, June 2005,
<https://www.rfc-editor.org/rfc/rfc4086>.
[RFC4987] Eddy, W., "TCP SYN Flooding Attacks and Common
Mitigations", RFC 4987, DOI 10.17487/RFC4987, August 2007,
<https://www.rfc-editor.org/rfc/rfc4987>.
[RFC792] Postel, J., "Internet Control Message Protocol", STD 5,
RFC 792, DOI 10.17487/RFC0792, September 1981,
<https://www.rfc-editor.org/rfc/rfc792>.
[RFC9293] Eddy, W., Ed., "Transmission Control Protocol (TCP)",
STD 7, RFC 9293, DOI 10.17487/RFC9293, August 2022,
<https://www.rfc-editor.org/rfc/rfc9293>.
8.2. Informative References
[CCS2020IPID]
Feng, X., Fu, C., Li, Q., Sun, K., and K. Xu, "Off-path
TCP exploits of the mixed IPID assignment", ACM Conference
on Computer and Communications Security (CCS) , 2020.
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[NDSS2022MTU]
Feng, X., Li, Q., Sun, K., Xu, K., Liu, B., Zheng, X.,
Yang, Q., Duan, H., and Z. Qian, "PMTUD is not Panacea:
Revisiting IP Fragmentation Attacks against TCP", Network
and Distributed System Security Symposium (NDSS) , 2022.
[SP2023MITM]
Feng, X., Li, Q., Sun, K., Yang, Y., and K. Xu, "Man-in-
the-middle attacks without rogue AP: When WPAs meet ICMP
redirects", IEEE Symposium on Security and Privacy (SP) ,
2023.
[USENIXSECURITY2023ICMP]
Feng, X., Li, Q., Sun, K., Qian, Z., Fu, C., Zhao, G.,
Kuang, X., and K. Xu, "Off-Path Network Traffic
Manipulation via Revitalized ICMP Redirect Attacks",
USENIX Security Symposium (Security) , 2023.
Acknowledgments
The authors would like to thank the IETF community, particularly
members of the INT-AREA working groups, for their valuable feedback
and insights during the development of this proposal.
Authors' Addresses
Ke Xu
Tsinghua University & Zhongguancun Laboratory
Beijing
China
Email: xuke@tsinghua.edu.cn
Xuewei Feng
Tsinghua University
Beijing
China
Email: fengxw06@126.com
Yuxiang Yang
Tsinghua University
Beijing
China
Email: yangyx22@mails.tsinghua.edu.cn
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Qi Li
Tsinghua University & Zhongguancun Laboratory
Beijing
China
Email: qli01@tsinghua.edu.cn
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