CVE-2026-10103

Mattermost versions affected: 11.7.x (up to 11.7.2), 11.6.x (up to 11.6.4), and 10.11.x (up to 10.11.19) have a flaw in the shared channel inbound sync handler that fails to verify post ownership. This allows an authenticated remote cluster to modify or delete posts authored by local users or oth...