CVE-2026-89949 batman-adv: dat: avoid unaligned fault in IP extraction
An unaligned memory access in the batman-adv kernel module can cause a system crash, requiring a kernel patch to fix.
- 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-2026-89949?
CVE-2026-89949 is a denial of service vulnerability in Linux, published on 16 Sep 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: dat: avoid unaligned fault in IP extraction
Independent of the alignment of the ARP packet in the SKB, either the batadv_arp_ip_src or the batadv_arp_ip_dst will have an unaligned access (on HW without native unaligned read support).
Use get_unaligned() to handle this properly on all architectures.
Which versions are affected by CVE-2026-89949?
How do I fix CVE-2026-89949?
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-2026-89949 being exploited?
There is no known exploitation of CVE-2026-89949 in the wild and no public exploit code.
Sources
Also known as AZL-101319, BELL-CVE-2026-89949, DEBIAN-CVE-2026-89949, GHSA-95x9-5832-jchc, UBUNTU-CVE-2026-89949.