Mattermost versions 9.9.x <= 9.9.0, 9.5.x <= 9.5.6, 9.7.x <= 9.7.5, 9.8.x <= 9.8.1 fail to properly validate synced posts, when shared channels are enabled, which allows a malicious remote to create/update/delete arbitrary posts in arbitrary channels
{ "cpes": [ "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*", "cpe:2.3:a:mattermost:mattermost_server:9.9.0:*:*:*:*:*:*:*" ], "severity": "High" }