CVE-2026-10819

Mattermost versions 11.6.x = 11.6.5, 10.11.x = 10.11.20, 11.8.x = 11.8.1, 11.7.x = 11.7.4 fail to limit the number of frames and enforce the file size cap on animated GIF uploads, which allows an authenticated attacker to cause a denial of service via a crafted animated GIF uploaded as a custom...