Mattermost versions 9.11.x <= 9.11.0 and 9.5.x <= 9.5.8 fail to validate that the message of the permalink post is a string, which allows an attacker to send a non-string value as the message of a permalink post and crash the frontend.
{ "cpes": [ "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*", "cpe:2.3:a:mattermost:mattermost_server:9.11.0:-:*:*:*:*:*:*", "cpe:2.3:a:mattermost:mattermost_server:9.11.0:rc1:*:*:*:*:*:*", "cpe:2.3:a:mattermost:mattermost_server:9.11.0:rc2:*:*:*:*:*:*", "cpe:2.3:a:mattermost:mattermost_server:9.11.0:rc3:*:*:*:*:*:*" ], "severity": "Medium" }