A concurrency bug in the Linux kernel’s openvswitch virtual port implementation causes a self‑deadlock when a tunnel port device is removed. The removal process waits for an RCU callback that never runs because the reference count is never released, leading to a permanent block and resource leak. If an administrator attempts to delete such a device, the kernel may hang, disrupting networking and related services.

The vulnerability exists in the Linux kernel’s openvswitch vport code. All distributions running an unpatched kernel that use tunnel or virtual ports are affected; the fix is present in kernel commits cited in the advisory but no specific version range is listed.

The CVSS score is 5.5 and the EPSS score is < 1%, indicating a low to moderate likelihood of exploitation, and the vulnerability is not listed in the CISA KEV catalog. The issue results in availability loss rather than a direct compromise. Exploitation requires the ability to delete a tunnel port device, a privilege normally reserved for users with network configuration rights or root access. Consequently the risk is moderate for systems relying on continuous networking uptime when local privileged access is present.