In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_u32: reject invalid shift counts u32_match_it() executes rule-supplied shift operands on a 32-bit value. A malformed u32 rule can provide a shift count of 32 or more, triggering an undefined shift out-of-bounds during packet evaluation. Validate XT_U32_LEFTSH and XT_U32_RIGHTSH operands in u32_mt_checkentry() and reject malformed rules before they reach the packet path.

A flaw was found in the Linux kernel's netfilter component, specifically in `xt_u32`. A local attacker with privileges to configure netfilter rules could craft a malicious `u32` rule with an invalid shift count. This could lead to an undefined shift out-of-bounds during packet evaluation, potentially causing a denial of service (DoS) or system instability.

Red Hat Enterprise Linux 10 Fix deferred kernel Red Hat Enterprise Linux 6 Out of support scope kernel Red Hat Enterprise Linux 7 Fix deferred kernel Red Hat Enterprise Linux 7 Fix deferred kernel-rt Red Hat Enterprise Linux 8 Fix deferred kernel Red Hat Enterprise Linux 8 Fix deferred kernel-rt Red Hat Enterprise Linux 9 Not affected kernel Red Hat Enterprise Linux 9 Not affected kernel-rt https://www.cve.org/CVERecord?id=CVE-2026-72350 https://nvd.nist.gov/vuln/detail/CVE-2026-72350 https://lore.kernel.org/linux-cve-announce/2026081512-CVE-2026-72350-e1f8@gregkh/T