CVE-2026-10819 — Mattermost Server Denial of Service via Animated GIF Emoji Upload
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 up…
Published: 2026-07-27 · CVSS: 6.5 · CVSS 3.1
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 emoji.. Mattermost Advisory ID: MMSA-2026-00695
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7