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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-63992 Detail

Description

In the Linux kernel, the following vulnerability has been resolved: tunnels: do not assume transport header in iptunnel_pmtud_check_icmp() In some cases, iptunnel_pmtud_check_icmp() can be called while skb transport header is not set. This triggers an out-of-bound access, because (typeof(skb->transport_header))~0U is 65535. Access the icmp header based on IPv4 network header, after making sure icmp->type is present in skb linear part. Note that iptunnel_pmtud_check_icmpv6()) is fine.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://git.kernel.org/stable/c/43368636c663cff6e59dde93cf4b8e43ac28eb93 kernel.org
https://git.kernel.org/stable/c/509323077ef79a26ba0c60bb556e45c12c398b2d kernel.org
https://git.kernel.org/stable/c/5a92cb45e34749865d03daf8d3500f77b5f6644c kernel.org
https://git.kernel.org/stable/c/7f4f7efe7f30edd29c4988de01728bf2398217e4 kernel.org
https://git.kernel.org/stable/c/a096b6e34f602950af9a2b0856cd93a5f4c276d7 kernel.org
https://git.kernel.org/stable/c/c7b7ec3e69e673c0d6b57f74d21da50c485c598e kernel.org
https://git.kernel.org/stable/c/cb549df9ce4ee15c9d5b19ddab12cf2128e4313c kernel.org
https://git.kernel.org/stable/c/e917d0c69f01af2bb4fbea2b66d560a53b3ac7ec kernel.org

Weakness Enumeration

CWE-ID CWE Name Source

Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-63992
NVD Published Date:
07/19/2026
NVD Last Modified:
07/20/2026
Source:
kernel.org