CVE-2026-31675 (GCVE-0-2026-31675)
Vulnerability from cvelistv5
Published
2026-04-25 08:46
Modified
2026-10-19 18:56
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_netem: fix out-of-bounds access in packet corruption In netem_enqueue(), the packet corruption logic uses get_random_u32_below(skb_headlen(skb)) to select an index for modifying skb->data. When an AF_PACKET TX_RING sends fully non-linear packets over an IPIP tunnel, skb_headlen(skb) evaluates to 0. Passing 0 to get_random_u32_below() takes the variable-ceil slow path which returns an unconstrained 32-bit random integer. Using this unconstrained value as an offset into skb->data results in an out-of-bounds memory access. Fix this by verifying skb_headlen(skb) is non-zero before attempting to corrupt the linear data area. Fully non-linear packets will silently bypass the corruption logic.
References
Impacted products
Vendor Product Version
Linux Linux Version: c865e5d99e25a171e8262fc0f7ba608568633c64
Version: c865e5d99e25a171e8262fc0f7ba608568633c64
Version: c865e5d99e25a171e8262fc0f7ba608568633c64
Version: c865e5d99e25a171e8262fc0f7ba608568633c64
Version: c865e5d99e25a171e8262fc0f7ba608568633c64
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