CVE-2026-72347

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.

References

• https://git.kernel.org/stable/c/1b47026fb4b35bac850ad6e8a4ad7fc018e09ebc
• https://git.kernel.org/stable/c/230173cc6105bdfb2696d37e6e56687b003fbe63
• https://git.kernel.org/stable/c/4eef84b09a3836919360c4232b0f16651a155eec
• https://git.kernel.org/stable/c/8ace320ac4416f5e5fbcd065309fb2dfcce787b0
• https://git.kernel.org/stable/c/9657bb11a6376ab0a79f05d433713d6944111e9d