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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-63994 Detail

Description

In the Linux kernel, the following vulnerability has been resolved: tunnels: load network headers after skb_cow() in iptunnel_pmtud_build_icmp[v6]() Sashiko found that iptunnel_pmtud_build_icmp() and iptunnel_pmtud_build_icmpv6() were caching ip_hdr() and ipv6_hdr() before an skb_cow() call which can reallocate skb->head. Fix this possible UAF by initializing the local variables after the skb_cow() call. Remove skb_reset_network_header() calls which were not needed.


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/50750d86a2e5266aba0c295483b3397843198b11 kernel.org
https://git.kernel.org/stable/c/6dff77899b9e9fe5d854abda3a98ad04e7229ef7 kernel.org
https://git.kernel.org/stable/c/7254aef4d1a7e18e887af9010e2f2dc34806789b kernel.org
https://git.kernel.org/stable/c/76cd9398a0470257ab765bdf5f358a2af2e17934 kernel.org
https://git.kernel.org/stable/c/95b6d772bfe788331d9742d73eaa12e113b2adc4 kernel.org
https://git.kernel.org/stable/c/b4bc94353050b1fa7b702bd4c6600710dd926cff kernel.org
https://git.kernel.org/stable/c/bf8b3f34c37c162357138e7c0942723b8b94fed1 kernel.org
https://git.kernel.org/stable/c/f3f204541f280a6ecb04503a0d6794d93990ca43 kernel.org

Weakness Enumeration

CWE-ID CWE Name Source

Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-63994
NVD Published Date:
07/19/2026
NVD Last Modified:
07/20/2026
Source:
kernel.org