CVE-2026-98559

A flaw was found in the Linux kernel's Shared Memory Communications (SMC) subsystem. When processing port errors, the kernel traverses active link groups without holding the appropriate lock, allowing a concurrent termination event to free memory while it is still in use. An attacker capable of inducing these concurrent network events could exploit this race condition to trigger a use-after-free flaw, leading to a Denial of Service (DoS) via a system crash.

This vulnerability is rated as Moderate impact for Red Hat Enterprise Linux because triggering the race condition requires precise timing during link group error handling, primarily leading to a denial of service via a kernel crash rather than arbitrary code execution. Furthermore, Shared Memory Communications (SMC) is not used by default in standard configurations and relies on RDMA-capable hardware or configured RoCE interfaces. Systems that do not utilize SMC or RoCE devices are not susceptible to this flaw.

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.