CVE-2024-40981 is a vulnerability in the Linux kernel's batman-adv module related to the function batadv_purge_orig_ref(). It involves bypassing empty buckets during the purge operation, which has been linked to soft lockups (CPU stalls) reported by syzbot. The root cause is not fully understood, but the issue causes the CPU to be stuck for extended periods, leading to system instability. The vulnerability has a medium severity with an impact on availability due to potential soft lockups. No specific affected versions or patch information is provided in the available data.