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Problem Statement for Cross-Layer Vulnerabilities due to Forged ICMP Errors
draft-xu-intarea-vulnerabilities-forged-icmp-01

The information below is for an old version of the document.
Document Type
This is an older version of an Internet-Draft whose latest revision state is "Active".
Expired & archived
Authors Ke Xu , Xuewei Feng , Li Qi , Zhaoxi Li
Last updated 2026-05-07 (Latest revision 2025-11-03)
RFC stream (None)
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Stream Stream state (No stream defined)
Consensus boilerplate Unknown
RFC Editor Note (None)
IESG IESG state Expired
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This Internet-Draft is no longer active. A copy of the expired Internet-Draft is available in these formats:

Abstract

ICMP error messages are vital for network reliability, providing feedback on issues such as unreachable hosts or fragmentation requirements. They help devices adapt dynamically, support troubleshooting, and enable essential functions like Path MTU Discovery. However, off-path attackers on the Internet may forge ICMP error messages to bypass legitimate validation mechanisms, causing the victim's TCP/IP stack to misinterpret network conditions and exposing critical vulnerabilities. This document analyzes how such forged ICMP errors can be exploited by off-path attackers to induce cross-layer interactions within the victim's TCP/IP stack, leading to four classes of vulnerabilities: information leakage, desynchronization of shared variables, semantic gaps, and identity deception. These ICMP-based attacks allow off-path attackers to manipulate network traffic, disrupt communication flows, and compromise both infrastructure and user privacy, without being on the direct communication path. The document concludes with proposed countermeasures and recommendations for protocol evolution.

Authors

Ke Xu
Xuewei Feng
Li Qi
Zhaoxi Li

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)