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
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Mattermost Mattermost
Default version status: unaffected
11.6.0 to ≤ 11.6.0affected11.5.0 to ≤ 11.5.2affected11.5.0 to ≤ 11.5.3affected11.4.0 to ≤ 11.4.4affected10.11.0 to ≤ 10.11.14affected11.7.0unaffected11.6.1unaffected11.5.3unaffected11.5.4unaffected11.4.5unaffected10.11.15unaffected