CVE-2026-93154

A flaw was found in the Linux kernel's RDMA/irdma component. This vulnerability allows a local user to deregister Memory Regions (MRs) that are actively backing Queue Pair (QP), Completion Queue (CQ), and Shared Receive Queue (SRQ) rings. By doing so, a malicious user could potentially disrupt network communication or cause system instability, leading to a denial of service.

The irdma driver did not pin the lifetime of user MRs that back QP/CQ/SRQ ring objects. A local process with access to RDMA uverbs could associate an MR with a user ring and then deregister that MR while the QP CQ or SRQ object still kept references to the backing PBL or MR state. This creates a use-after-free candidate rather than a simple resource leak, because later destroy resize or queue handling paths may touch memory whose owning MR lifetime has ended. For the CVSS the PR:L is used because reliable triggering requires local code execution with access to the RDMA uverbs device, but it does not require full administrator privileges in systems where RDMA access is delegated to users or service accounts. The issue is not directly network reachable because a remote peer cannot deregister the local MR by itself. Impact is at least local denial of service via kernel crash and in the paranoid case may include confidentiality and integrity impact due to possible memory corruption or privilege escalation.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.