The vulnerability stems from an unnecessary rcu_barrier call in the Linux kernel’s br_multicast_dev_del() function, which caused excessive RTNL (routing table) pressure and stalled kernel tasks. The removal of this barrier prevents long waiting times on mutexes and stops the kernel from being blocked in the net namespace cleanup workqueue, mitigating a potential system freeze. The impact is a denial‑of‑service that can lead to unresponsive kernel state in real‑time or heavily loaded environments. Based on the description, it is inferred that exploitation requires local execution with sufficient privileges to perform network device teardown or bridge reconfiguration.

The issue affects all Linux systems that run the original kernel code before the patch was applied; the fix is implemented in updated kernel releases rather than on a per‑vendor basis.

The exploitability is low to moderate because the flaw only manifests when the br_multicast_dev_del() path is executed, typically during network device teardown or bridge reconfiguration. The CVSS score of 5.5 reflects moderate severity, and the EPSS score of < 1% indicates a very low likelihood of exploitation in the wild. No known public exploitation exists and the CVE is not listed in the CISA KEV catalog. However, the kernel freeze behavior could be triggered by a malicious or misbehaving local process that performs network operations, making it a significant local denial‑of‑service risk. The likely attack vector is local privileged network manipulation.