What is GHSA-x274-8qfc-hrgf?

GHSA-x274-8qfc-hrgf is a security advisory published by GitHub Security Advisories with Low severity. Mattermost MS Teams plugin doesn't limit the request body size on the /lifecycle webhook endpoint

Which CVE IDs does GHSA-x274-8qfc-hrgf cover?

GHSA-x274-8qfc-hrgf covers the following CVE IDs: CVE-2026-21388. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

What is the CVSS v3 score of GHSA-x274-8qfc-hrgf?

GHSA-x274-8qfc-hrgf has a CVSS v3 base score of 3.7, published by GitHub Security Advisories.

Which products are affected by GHSA-x274-8qfc-hrgf?

GHSA-x274-8qfc-hrgf affects 1 product, including: go/github.com/mattermost/mattermost-plugin-msteams:\u003c 1.15.1-0.20260213190728-6fe4d295592e.

GHSA-x274-8qfc-hrgfLowCVSS 3.7

Mattermost MS Teams plugin doesn't limit the request body size on the /lifecycle webhook endpoint

Vendor

GitHub Security Advisories

Published

April 9, 2026

Last Modified

April 29, 2026

🔗 CVE IDs covered (1)

CVE-2026-21388 →

📋 Description

Mattermost Plugins versions <=2.3.1 fail to limit the request body size on the {{/lifecycle}} webhook endpoint which allows an authenticated attacker to cause memory exhaustion and denial of service via sending an oversized JSON payload. Mattermost Advisory ID: MMSA-2026-00610.

🎯 Affected products1

go/github.com/mattermost/mattermost-plugin-msteams:< 1.15.1-0.20260213190728-6fe4d295592e

🔗 References (5)

https://nvd.nist.gov/vuln/detail/CVE-2026-21388
https://mattermost.com/security-updates
https://github.com/mattermost/mattermost-plugin-msteams/commit/6fe4d295592ecc8767d67e69286cbeec01be3210
https://github.com/mattermost/mattermost-plugin-msteams/releases/tag/v2.3.2
https://github.com/advisories/GHSA-x274-8qfc-hrgf