The Linux kernel’s RDMA rtrs-clt client module contains a race condition that allows a connection handler to acquire Completion Queue credits before the remote peer is fully connected. If the connection attempt is interrupted, the client may skip properly freeing those credits, causing a leak in the CQ pool. Over time the leaked credits could accumulate, triggering a WARN_ON during cleanup and potentially exhausting kernel resources, which degrades performance or leads to a denial of service.

All Linux systems running a kernel that includes the unpatched RDMA rtrs-clt client module are affected. The vulnerability is tied to the general Linux kernel, not a particular distribution, so any kernel version prior to the patch can be impacted.

The CVSS score of 5.5 indicates moderate severity, while the EPSS score of < 1% reflects a low likelihood of exploitation. The vulnerability is not listed in the CISA KEV catalog, suggesting no public exploitation. Based on the description, it is inferred that an attacker could exploit this race condition by repeatedly initiating and aborting RDMA connections to trigger the leak; the attack could be local if the attacker controls a process that uses the RDMA client, or remote if the RDMA service is exposed to untrusted clients. Successful exploitation would lead to resource exhaustion and possible denial of service.