CVE-2026-43252

A flaw was found in the MultiPath TCP (MPTCP) subsystem of the Linux kernel. A local attacker could exploit a logic error in how MPTCP manages network connection endpoints. By performing a specific sequence of operations, an attacker could trigger a kernel warning, potentially leading to system instability or a denial of service (DoS).

This vulnerability is rated as Moderate severity because exploitation is restricted to local users capable of configuring network endpoints, and the blast radius is limited to a kernel warning without compromising data integrity or confidentiality. Triggering the condition requires an uncommon sequence of endpoint re-allocations and flag updates during active connections, which could lead to a denial of service if warnings cause the system to panic. Earlier Red Hat Enterprise Linux releases are not affected because the vulnerable path management logic was introduced in later upstream kernels.

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.