CVE-2026-63994

CVE CVE-2026-63994EUVD EUVD-2026-45567Published 2026-07-19T14:56:13.000ZLast changed 2026-08-05T12:37:58.000ZCVSS 9.8

What the advisory describes

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.

Source: EUVD (ENISA), in the words of the advisory.

Products the advisory names

These come from the advisory itself, not from any check we performed.

Linux — Linux patch: 7.0.12; 5.9; 4cb47a8644cc9eb8ec81190a50e79e6530d0297f <b4bc94353050b1fa7b702bd4c6600710dd926cff; patch: 6.1.176; patch: 7.1; patch: 5.15.210; 4cb47a8644cc9eb8ec81190a50e79e6530d0297f <95b6d772bfe788331d9742d73eaa12e113b2adc4; patch: 0; patch: 6.12.93; 4cb47a8644cc9eb8ec81190a50e79e6530d0297f <6dff77899b9e9fe5d854abda3a98ad04e7229ef7; 4cb47a8644cc9eb8ec81190a50e79e6530d0297f <76cd9398a0470257ab765bdf5f358a2af2e17934; 4cb47a8644cc9eb8ec81190a50e79e6530d0297f <50750d86a2e5266aba0c295483b3397843198b11; 4cb47a8644cc9eb8ec81190a50e79e6530d0297f <f3f204541f280a6ecb04503a0d6794d93990ca43; patch: 5.10.259; patch: 6.18.35; patch: 6.6.143; 4cb47a8644cc9eb8ec81190a50e79e6530d0297f <7254aef4d1a7e18e887af9010e2f2dc34806789b; 4cb47a8644cc9eb8ec81190a50e79e6530d0297f <bf8b3f34c37c162357138e7c0942723b8b94fed1

The versions shown are the advisory's own. Patchlage compares no version numbers and derives no judgement from them — which version is installed is something a person has to look up.

Carried in the product catalogue

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Linux — Linux

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