EUVD-2026-49254
GHSA-qf49-6jm2-h67m
Severity by source
AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Primary rating from Vendor (Mattermost) · only source for this CVE.
CVSS VectorVendor: Mattermost
Lifecycle Timeline
1DescriptionCVE.org
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
AnalysisAI
Denial of service vulnerability in Mattermost allows authenticated users to exhaust server resources by uploading crafted animated GIFs as custom emoji. Affects versions 10.11.x, 11.6.x, 11.7.x, and 11.8.x up to certain patch levels. No active exploitation or public exploit is known, but patches are available from the vendor.
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Same technique Denial Of Service
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External POC / Exploit Code
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