NetSight
medium5.5

CVE-2026-52916

In the Linux kernel, the following vulnerability has been resolved: batman-adv: frag: disallow unicast fragment in fragment batadv_frag_skb_buffer() is called …

Impact

In the Linux kernel, the following vulnerability has been resolved: batman-adv: frag: disallow unicast fragment in fragment batadv_frag_skb_buffer() is called by batadv_batman_skb_recv() when a BATADV_UNICAST_FRAG packet is received. Once all fragments are collected and the packet is reassembled, batadv_recv_frag_packet() calls batadv_batman_skb_recv() again to process the defragmented payload. A malicious sender can craft a BATADV_UNICAST_FRAG packet whose reassembled payload is itself a BATADV_UNICAST_FRAG packet (matryoshka-style nesting). Each nesting level recurses through batadv_batman_skb_recv() without bound, growing the kernel stack until it is exhausted. Since refragmentation or fragments in fragments are not actually allowed, discard all packets which are still BATADV_UNICAST_FRAG packets after the defragmentation process.

Affected products

VendorProductAffected versions
LinuxLinux Kernel
from 3.13 before 5.10.258
from 5.11 before 5.15.209
from 5.16 before 6.1.175
from 6.2 before 6.6.142
from 6.7 before 6.12.92
from 6.13 before 6.18.34

References