A vulnerability described as critical has been identified in Mattermost up to 10.11.14/11.4.4/11.5.3/11.6.0 . This affects an unknown function. Executing a manipulation of the argument Scope can lead to incorrect authorization. This vulnerability is registered as CVE-2026-28735 . It is possible to launch the attack remotely. No exploit is available. Upgrading the affected component is recommended.