CVE-2026-25780

Medium

Description

Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to bound memory allocation when processing DOC files which allows an authenticated attacker to cause server memory exhaustion and denial of service via uploading a specially crafted DOC file.. Mattermost Advisory ID: MMSA-2026-00581

SeverityMedium
CVSS4.3
Exploit probability—
ProductMattermost Server
PublishedMar 16, 2026
First seenMar 16, 2026
Weakness typeCWE-789CWE-789

How to fix

Update
  • mattermost mattermost_server10.11.11, 11.2.3, 11.3.1 or later
  • github.com/mattermost/mattermost/server/v88.0.0-20260123215601-86797c508c44 or later
  • github.com/mattermost/mattermost-server5.3.2-0.20260123215601-86797c508c44, 10.11.11, 11.2.3, 11.3.1, 10.11.11+incompatible, 11.2.3+incompatible, 11.3.1+incompatible or later

Affected products

ProductAffected versionsFixed in
mattermost mattermost_server10.11.0 ≤ v < 10.11.11, 11.2.0 ≤ v < 11.2.3, 11.3.0 ≤ v < 11.3.110.11.11, 11.2.3, 11.3.1
github.com/mattermost/mattermost/server/v8Gov < 8.0.0-20260123215601-86797c508c448.0.0-20260123215601-86797c508c44
github.com/mattermost/mattermost-serverGov < 5.3.2-0.20260123215601-86797c508c44, 10.11.0-rc1 ≤ v < 10.11.11, 11.2.0-rc1 ≤ v < 11.2.3, 11.3.0-rc1 ≤ v < 11.3.1, 10.11.0-rc1+incompatible ≤ v < 10.11.11+incompatible, 11.2.0-rc1+incompatible ≤ v < 11.2.3+incompatible, 11.3.0-rc1+incompatible ≤ v < 11.3.1+incompatible5.3.2-0.20260123215601-86797c508c44, 10.11.11, 11.2.3, 11.3.1, 10.11.11+incompatible, 11.2.3+incompatible, 11.3.1+incompatible
github.com/mattermost/mattermost-server/v5GoNo range specified—
github.com/mattermost/mattermost-server/v6GoNo range specified—

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