CVE-2026-98252

A flaw was found in the Linux kernel's Remote Direct Memory Access (RDMA) subsystem. This flaw allows a local attacker to cause a denial of service (DoS) due to a race condition in the iWARP port mapper component. Because request structures are added to a shared tracking list before their reference counters are initialized, concurrent access from another processor core can manipulate uninitialized reference counts and trigger a kernel crash.

This vulnerability is rated as Moderate severity because exploitation requires local access, relies on winning a narrow timing window between concurrent execution threads, and results in a kernel crash causing a denial of service rather than privilege escalation. In typical Red Hat Enterprise Linux environments, RDMA and iWARP network services represent specialized high-performance stacks that are not configured or active on default installations. Systems that do not configure or use iWARP RDMA interfaces do not invoke the affected port mapper Netlink routines, significantly constraining the operational blast radius.

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.