CVE-2026-93849 Mattermost allows authenticated users to trigger excessive memory allocation via crafted msgpack binary WebSocket frames

Mattermost versions 11.9.x = 11.9.1, 11.8.x = 11.8.5, 11.7.x = 11.7.10, 11.10.x = 11.10.1 Mattermost fail to apply allocation limits to the byte-string decode paths in its WebSocket msgpack decoder, which allows an authenticated remote attacker to cause excessive server memory allocation via a...