CVE-2026-72235 batman-adv: retrieve ethhdr after potential skb realloc on RX
A use-after-free vulnerability in the Linux kernel's batman-adv module allows attackers to cause denial of service or execute arbitrary code via crafted network packets.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-72235?
CVE-2026-72235 is a high-severity use after free 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: retrieve ethhdr after potential skb realloc on RX
pskb_may_pull() in batadv_interface_rx() could reallocate the buffer behind the skb. Variables which were pointing to the old buffer need to be reassigned to avoid an use-after-free.
This was done correctly for the VLAN header but missed for the ethernet header which is later used for the TT and AP isolation handling.
Which versions are affected by CVE-2026-72235?
How do I fix CVE-2026-72235?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-72235 being exploited?
There is no known exploitation of CVE-2026-72235 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-72235, DEBIAN-CVE-2026-72235, GHSA-wgqg-h53f-2jvm, UBUNTU-CVE-2026-72235.