CVE-2026-72232 batman-adv: ensure minimal ethernet header on TX
A local attacker with eBPF access can trigger an out-of-bounds read in the batman-adv kernel module, potentially causing a crash or code execution.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-72232?
CVE-2026-72232 is a high-severity memory corruption vulnerability in Linux, published on 15 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
batman-adv: ensure minimal ethernet header on TX
As documented in commit 8bd67ebb50c0 ("net: bridge: xmit: make sure we have at least eth header len bytes"), it is possible by for a local user with eBPF TC hook access to attach a tc filter which truncates the packet and redirects to an batadv interface. But the code assumes that at least ETH_HLEN bytes are available and thus might read outside of the available buffer.
The batadv_interface_tx() must therefore always check itself if enough data is available for the ethernet header and don't rely on min_header_len.
Which versions are affected by CVE-2026-72232?
How do I fix CVE-2026-72232?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-72232 being exploited?
There is no known exploitation of CVE-2026-72232 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-72232, DEBIAN-CVE-2026-72232, GHSA-348f-jxjq-8xpv, UBUNTU-CVE-2026-72232.