CVE-2026-46137

A flaw was found in the Linux kernel, specifically within the Multipath TCP (MPTCP) implementation. The mptcp_pm_add_timer() helper, which is executed as a timer callback, does not properly hold the socket lock when operating in a softirq context. This oversight can lead to a potential data race, which may result in unpredictable system behavior or instability.

This vulnerability is rated as Moderate severity for Red Hat Enterprise Linux because exploitation is restricted to a denial of service and necessitates local user privileges or active Multipath TCP (MPTCP) traffic to trigger the race condition. Standard enterprise installations rarely utilize MPTCP for core network workloads, significantly constraining practical exposure. Triggering the flaw requires asynchronous timer callbacks on MPTCP path management operations, causing kernel instability or deadlocks rather than unauthorized code execution 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.