GitHub Advisoryadvisory · Go

GHSA-jmvr-r5hm-fxfr Mattermost doesn't enforce request body size limits on plugin HTTP endpoints

HIGH Published 2026-05-26 Modified 2026-06-29 Official page ↗
Aliases
CVE-2026-5308
Ecosystem
Go
Packages
github.com/mattermost/mattermost-server, github.com/mattermost/mattermost-plugin-github
Severity
High
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weaknesses
CWE-400
Reviewed
2026-06-29

Affected packages

• Go github.com/mattermost/mattermost-server: >= 11.6.0, < 11.6.1 → fixed in 11.6.1 • Go github.com/mattermost/mattermost-server: >= 11.5.0, < 11.5.4 → fixed in 11.5.4 • Go github.com/mattermost/mattermost-server: >= 11.4.0, < 11.4.5 → fixed in 11.4.5 • Go github.com/mattermost/mattermost-server: >= 10.11.0, < 10.11.15 → fixed in 10.11.15 • Go github.com/mattermost/mattermost-plugin-github: < 1.0.1-0.20260410143745-9b41b1fd43c4 → fixed in 1.0.1-0.20260410143745-9b41b1fd43c4

Description

Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to enforce request body size limits on plugin HTTP endpoints which allows an attacker to cause a denial of service via crafted oversized HTTP requests.. Mattermost Advisory ID: MMSA-2026-00646

Related

Alias · CVE (1)

  • CVE-2026-5308 Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to enforce request body size limits on… vulnerability

Weakness · CWE (1)

  • CWE-400 Uncontrolled Resource Consumption weakness

References