CVE-2026-4635 | Mattermost up to 10.11.14/11.4.4/11.5.3/11.6.0 Notification Message race condition

A vulnerability was found in Mattermost up to 10.11.14/11.4.4/11.5.3/11.6.0. It has been classified as problematic. This vulnerability affects unknown code of the component Notification Message Handler. Performing a manipulation results in race condition.

This vulnerability is identified as CVE-2026-4635. The attack can be initiated remotely. There is not any exploit available.

Upgrading the affected component is recommended.