CVE-2026-72231 batman-adv: tt: avoid request storms during pending request
A logic error in the batman-adv kernel module allows attackers to trigger request storms, causing denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-72231?
CVE-2026-72231 is a high-severity denial of service vulnerability in Linux, published on 15 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
batman-adv: tt: avoid request storms during pending request
batadv_send_tt_request() allocates a tt_req_node when none exists for the destination originator node. This should prevent that a multiple TT requests are send at the same time to an originator.
But if allocation of the send buffer failed, this request must be cleaned up again. But indicator for such a failure is "ret == false". But the actual implementation is checking for "ret == true".
The check must be inverted to not loose the information about the TT request directly after it was attempted to be sent out. This should avoid potential request storms.
Which versions are affected by CVE-2026-72231?
How do I fix CVE-2026-72231?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-72231 being exploited?
There is no known exploitation of CVE-2026-72231 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-72231, DEBIAN-CVE-2026-72231, GHSA-r9hr-vqwf-9q7r, UBUNTU-CVE-2026-72231.