CVEvulnerability
CVE-2026-74747
7.8 HIGH
Official page ↗
- Status
- Received
- Published
- 2026-08-26
- Last modified
- 2026-10-21
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- CVSS 3.1 (416baaa9-dc9f-4396-8d5f-8c081fb06d67)
- 7.8 HIGH — CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Description
In the Linux kernel, the following vulnerability has been resolved:
ipvs: revalidate ihl to prevent out-of-bounds access
While the outer IP header is already pulled into the skb head,
we must be careful and revalidate the embedded headers after
reading them from the skb frags to prevent out-of-bounds
access.
One such place reported by Sashiko is ip_vs_nat_icmp() where
local process can change the ihl field and after
skb_ensure_writable() we can see larger value which is a
problem for the ip_send_check(cih) calls.
Add check to drop the packet if the ihl field is changed.
References
- https://git.kernel.org/stable/c/041b2303c8019394735c1f76c5138657bf660a7d git.kernel.org
- https://git.kernel.org/stable/c/2512289cbf58706fd558e8fccea4e28003a2af54 git.kernel.org
- https://git.kernel.org/stable/c/5365f012451fce2453f13a568dcb72ea534c1e4d git.kernel.org
- https://git.kernel.org/stable/c/d93660df4dd1d116f608ada4a29a80a5d6f0a6ed git.kernel.org
- https://git.kernel.org/stable/c/eb81c8e758f49e04391f77d9470a6232bb5f1c7a git.kernel.org