An issue was discovered in Mattermost Server before 5.12.0. Use of a Proxy HTTP header, rather than the source address in an IP packet header, for obtaining IP address information was mishandled.
An issue was discovered in Mattermost Server before 5.10.0, 5.9.1, 5.8.2, and 4.10.9. A non-member could change the Update/Patch Channel endpoint for a private channel.
An issue was discovered in Mattermost Server before 5.10.0. An attacker can bypass the intended appearance of the Edited flag after changing a post's file ID.
An issue was discovered in Mattermost Server before 5.17.0. It allows remote attackers to cause a denial of service (client-side application crash) via a LaTeX message.
An issue was discovered in Mattermost Server before 5.16.1, 5.15.2, 5.14.5, and 5.9.6. It allows attackers to obtain sensitive information (local files) during legacy attachment migration.
An issue was discovered in Mattermost Server before 5.16.0. It allows attackers to cause a denial of service (markdown renderer hang) via many backtick characters.
An issue was discovered in Mattermost Server before 5.15.0. It allows attackers to cause a denial of service (CPU consumption) via crafted characters in a SQL LIKE clause to an APIv4 endpoint.