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.
Fix
Patch, vendor advisory and mitigation references on NVD 8
- https://git.kernel.org/stable/c/43368636c663cff6e59dde93cf4b8e43ac28eb93 Patch
- https://git.kernel.org/stable/c/509323077ef79a26ba0c60bb556e45c12c398b2d Patch
- https://git.kernel.org/stable/c/5a92cb45e34749865d03daf8d3500f77b5f6644c Patch
- https://git.kernel.org/stable/c/7f4f7efe7f30edd29c4988de01728bf2398217e4 Patch
- https://git.kernel.org/stable/c/a096b6e34f602950af9a2b0856cd93a5f4c276d7 Patch
- https://git.kernel.org/stable/c/c7b7ec3e69e673c0d6b57f74d21da50c485c598e Patch
- https://git.kernel.org/stable/c/cb549df9ce4ee15c9d5b19ddab12cf2128e4313c Patch
- https://git.kernel.org/stable/c/e917d0c69f01af2bb4fbea2b66d560a53b3ac7ec Patch
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 2
- StatusAnalyzed → ModifiedNVD modified 2026-10-19 21:17
- First seenCVSS 9.1 · linuxNVD modified 2026-10-16 16:19
Affected (CPE criteria) 6
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:*
References 8
- https://git.kernel.org/stable/c/43368636c663cff6e59dde93cf4b8e43ac28eb93 Patch
- https://git.kernel.org/stable/c/509323077ef79a26ba0c60bb556e45c12c398b2d Patch
- https://git.kernel.org/stable/c/5a92cb45e34749865d03daf8d3500f77b5f6644c Patch
- https://git.kernel.org/stable/c/7f4f7efe7f30edd29c4988de01728bf2398217e4 Patch
- https://git.kernel.org/stable/c/a096b6e34f602950af9a2b0856cd93a5f4c276d7 Patch
- https://git.kernel.org/stable/c/c7b7ec3e69e673c0d6b57f74d21da50c485c598e Patch
- https://git.kernel.org/stable/c/cb549df9ce4ee15c9d5b19ddab12cf2128e4313c Patch
- https://git.kernel.org/stable/c/e917d0c69f01af2bb4fbea2b66d560a53b3ac7ec Patch