CVE-2026-19600 Mattermost logs plaintext authentication tokens in debug-level server logs on failed auth attempts

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 fail to sanitize authentication tokens before writing them to server log entries, which allows an attacker with access to server logs to obtain valid session tokens or OAuth access tokens and impersonate...