In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_tcpmss: check remaining length before reading optlen Quoting reporter: In net/netfilter/xt_tcpmss.c (lines 53-68), the TCP option parser reads op[i+1] directly without validating the remaining option length. If the last byte of the option field is not EOL/NOP (0/1), the code attempts to index op[i+1]. In the case where i + 1 == optlen, this causes an out-of-bounds read, accessing memory past the optlen boundary (either reading beyond the stack buffer _opt or the following payload).
Fix
Patch, vendor advisory and mitigation references on NVD 8
- https://git.kernel.org/stable/c/07a9b32eaae792ff7d0fcac14d8920c937c0a9c3 Patch
- https://git.kernel.org/stable/c/5e13d0a37666955b6cfddc0f73cb40ed645b8a05 Patch
- https://git.kernel.org/stable/c/735ee8582da3d239eb0c7a53adca61b79fb228b3 Patch
- https://git.kernel.org/stable/c/8b300f726640c48c3edfe9c453334dd801f4b74e Patch
- https://git.kernel.org/stable/c/cd5beda7e0e32865e214f28034bb92c1cecff885 Patch
- https://git.kernel.org/stable/c/eaedc0bc18be46fe7f58170e967959a932c4f824 Patch
- https://git.kernel.org/stable/c/f6c412dcfd76b0516d51aa847d8f4c7b70381b09 Patch
- https://git.kernel.org/stable/c/f895191dc32c53eaf443b6443fe40945b2f92287 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 20:18
- First seenCVSS 8.2 · linuxNVD modified 2026-10-16 16:17
Affected (CPE criteria) 7
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:2.6.12:-:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:2.6.12:rc2:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:2.6.12:rc3:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:2.6.12:rc4:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:2.6.12:rc5:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:2.6.12:rc6:*:*:*:*:*:*
References 8
- https://git.kernel.org/stable/c/07a9b32eaae792ff7d0fcac14d8920c937c0a9c3 Patch
- https://git.kernel.org/stable/c/5e13d0a37666955b6cfddc0f73cb40ed645b8a05 Patch
- https://git.kernel.org/stable/c/735ee8582da3d239eb0c7a53adca61b79fb228b3 Patch
- https://git.kernel.org/stable/c/8b300f726640c48c3edfe9c453334dd801f4b74e Patch
- https://git.kernel.org/stable/c/cd5beda7e0e32865e214f28034bb92c1cecff885 Patch
- https://git.kernel.org/stable/c/eaedc0bc18be46fe7f58170e967959a932c4f824 Patch
- https://git.kernel.org/stable/c/f6c412dcfd76b0516d51aa847d8f4c7b70381b09 Patch
- https://git.kernel.org/stable/c/f895191dc32c53eaf443b6443fe40945b2f92287 Patch