Description
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).
Affected products
linux: linux kernel
References8
- git.kernel.org/stable/c/07a9b32eaae792ff7d0fcac14d8920c937c0a9c3 Patch
- git.kernel.org/stable/c/5e13d0a37666955b6cfddc0f73cb40ed645b8a05 Patch
- git.kernel.org/stable/c/735ee8582da3d239eb0c7a53adca61b79fb228b3 Patch
- git.kernel.org/stable/c/8b300f726640c48c3edfe9c453334dd801f4b74e Patch
- git.kernel.org/stable/c/cd5beda7e0e32865e214f28034bb92c1cecff885 Patch
- git.kernel.org/stable/c/eaedc0bc18be46fe7f58170e967959a932c4f824 Patch
- git.kernel.org/stable/c/f6c412dcfd76b0516d51aa847d8f4c7b70381b09 Patch
- git.kernel.org/stable/c/f895191dc32c53eaf443b6443fe40945b2f92287 Patch
Metrics
- CVSS 3.1
-
8.2
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H - EPSS — exploit probability
- 0% percentile: 41 · as of 13 November 2026
- CWE
- CWE-125
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