CVE-2026-46170

A flaw was found in the Linux kernel's Multipath TCP (MPTCP) implementation. When an ADD_ADDR message is retransmitted, an issue in socket (sk) reference counting can prevent the socket from being properly freed. This improper resource management may lead to a Denial of Service (DoS) condition, where the system could become unresponsive due to indefinite waiting during timer synchronization.

This vulnerability is rated as Moderate severity for Red Hat Enterprise Linux because exploitation requires an active Multipath TCP (MPTCP) connection and can trigger an indefinite wait within kernel timer handling, leading to a local denial of service without compromising confidentiality or integrity. Standard network traffic does not utilize MPTCP sockets unless applications explicitly request the protocol or specific path-manager rules are configured. Consequently, system exposure is constrained to environments where multipath routing features are actively engaged.

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.