CVE-2026-68290

A flaw was found in the Linux kernel's Reliable Datagram Sockets (RDS) TCP implementation. A race condition can occur during network namespace teardown, where a concurrent system control (sysctl) write operation attempts to access a socket that has already been freed. This use-after-free vulnerability can lead to system instability or a denial of service.

This vulnerability is rated as Important severity rather than Moderate because an unprivileged local user with network namespace creation capabilities can reliably trigger the race condition to corrupt kernel memory, which can lead to privilege escalation or complete system termination. While Reliable Datagram Sockets over TCP is not used in standard configurations, the protocol module can be autoloaded upon request by unprivileged processes in environments where unprivileged user namespaces are enabled. Consequently, systems running default installations may be exposed if unprivileged namespace manipulation is permitted.

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.