CVE-2026-11993

Medium

Description

Mattermost versions 11.9.x <= 11.9.0, 11.8.x <= 11.8.4, 11.7.x <= 11.7.7, 10.11.x <= 10.11.22 fail to properly enforce the limit of concurrent files being processed and handled failed files, which allows a user with permission to upload files to spawn more goroutines than intended and block the indexing of other files via uploading heavy files constantly to the server.. Mattermost Advisory ID: MMSA-2026-00696

SeverityMedium
CVSS4.3
Exploit probability—
ProductMattermost Server
PublishedSep 14, 2026
First seenSep 14, 2026

How to fix

Update
  • mattermost mattermost_server10.11.23, 11.7.8, 11.8.5, 11.9.1 or later

Affected products

ProductAffected versionsFixed in
mattermost mattermost_server10.11.0 ≤ v < 10.11.23, 11.7.0 ≤ v < 11.7.8, 11.8.0 ≤ v < 11.8.5, 11.9.0 ≤ v < 11.9.110.11.23, 11.7.8, 11.8.5, 11.9.1

Check your version

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