CVE-2026-98099

A flaw was found in the Linux kernel. A local user could exploit a race condition in the IPv6 multicast subsystem to cause a Denial of Service (DoS) or kernel memory corruption. Because internal multicast lists are modified without proper synchronization helpers, concurrent socket operations can race with active reader threads, leaving list pointers in an inconsistent state and causing a system crash.

This vulnerability is evaluated as a Moderate impact because exploiting this race condition requires local unprivileged system access and primarily results in a kernel crash (denial of service), without granting unauthorized privilege escalation or remote access. While IPv6 networking is enabled by default across Red Hat Enterprise Linux environments, triggering the defect depends on precisely timed concurrent socket operations that manipulate multicast group memberships alongside active packet processing. Consequently, the blast radius is restricted to local service availability disruptions on multi-tenant systems or containerized workloads sharing the host kernel.

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.