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MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Description
Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.2, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to validate the TIFF IFD offset in the image header before allocating memory, which allows authenticated users with file upload or posting permissions to cause a denial of service (server OOM) via uploading a crafted TIFF file or posting a URL that serves one.. Mattermost Advisory ID: MMSA-2026-00648
Basic Information
ID
CVE-2026-5755
Source
Mattermost
Published
May 22, 2026 at 10:18
Modified
May 22, 2026 at 12:15
Affected Product
Vendor
Mattermost
Product
Mattermost
Version
11.6.0
Affected Versions
Mattermost Mattermost 11.6.0
Mattermost Mattermost 11.5.0
Mattermost Mattermost 11.5.0
Mattermost Mattermost 11.4.0
Mattermost Mattermost 10.11.0
Mattermost Mattermost 11.5.0
Mattermost Mattermost 11.5.0
Mattermost Mattermost 11.4.0
Mattermost Mattermost 10.11.0