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.
Affected products
linux: linux kernel
References8
- git.kernel.org/stable/c/43368636c663cff6e59dde93cf4b8e43ac28eb93 Patch
- git.kernel.org/stable/c/509323077ef79a26ba0c60bb556e45c12c398b2d Patch
- git.kernel.org/stable/c/5a92cb45e34749865d03daf8d3500f77b5f6644c Patch
- git.kernel.org/stable/c/7f4f7efe7f30edd29c4988de01728bf2398217e4 Patch
- git.kernel.org/stable/c/a096b6e34f602950af9a2b0856cd93a5f4c276d7 Patch
- git.kernel.org/stable/c/c7b7ec3e69e673c0d6b57f74d21da50c485c598e Patch
- git.kernel.org/stable/c/cb549df9ce4ee15c9d5b19ddab12cf2128e4313c Patch
- git.kernel.org/stable/c/e917d0c69f01af2bb4fbea2b66d560a53b3ac7ec Patch
Metrics
- CVSS 3.1
-
9.1
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H - EPSS — exploit probability
- 1% percentile: 44 · as of 14 November 2026
- CWE
- CWE-125
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