Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_connmark: reject invalid shift parameters Revision 2 of the CONNMARK target accepts user-controlled shift parameters and applies them to 32-bit mark values in connmark_tg_shift(). A shift_bits value of 32 or more triggers an undefined-shift bug when the rule is evaluated. Invalid shift_dir values are also accepted and silently fall back to the left-shift path. Reject invalid revision-2 shift parameters in connmark_tg_check() so malformed rules fail at installation time, before they can reach the packet path.
References7
- git.kernel.org/stable/c/1b47026fb4b35bac850ad6e8a4ad7fc018e09ebc
- git.kernel.org/stable/c/230173cc6105bdfb2696d37e6e56687b003fbe63
- git.kernel.org/stable/c/4eef84b09a3836919360c4232b0f16651a155eec
- git.kernel.org/stable/c/8ace320ac4416f5e5fbcd065309fb2dfcce787b0
- git.kernel.org/stable/c/9657bb11a6376ab0a79f05d433713d6944111e9d
- git.kernel.org/stable/c/c3fa852d117b3fda72265e4230e3967db4a74fcf
- git.kernel.org/stable/c/d8ce63d928b457fba7ed1e302492dfd32293671c
Metrics
- CVSS 3.1
-
7.3
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:H - EPSS — exploit probability
- 0% percentile: 7 · as of 11 November 2026
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