CVE-2025-21812

Summary

CVE-2025-21812 is a locking issue in the Linux kernel's ax25 driver. The vulnerability was discovered by SYZbot and involves a circular locking dependency between the rtl_mutex and sk_lock-AF_AX25. This dependency can result in a deadlock situation where two different tasks attempt to acquire the respective locks in a conflicting order. To mitigate the issue, it is recommended to remove the ax25 RTNL dependency in ax25_setsockopt(). The vulnerability was identified during testing with the syzkaller fuzzer and was confirmed on a 6.13.0-rc3 kernel. The provided call trace indicates that the syz.5.1818 process was involved in the deadlock.

Prevent cyber attacks with Recorded Future by prioritizing and patching critical vulnerabilities being exploited by threat actors targeting your industry. Book your demo to learn more.