What is GHSA-6mc8-c94m-mjg8?

GHSA-6mc8-c94m-mjg8 is a security advisory published by GitHub Security Advisories with Medium severity. Mattermost versions 11.9.x \u003c= 11.9.0, 11.8.x \u003c= 11.8.4, 11.7.x \u003c= 11.7.8, 10.11.x \u003c= 10.11.22...

Which CVE IDs does GHSA-6mc8-c94m-mjg8 cover?

GHSA-6mc8-c94m-mjg8 covers the following CVE IDs: CVE-2026-86349. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

What is the CVSS v3 score of GHSA-6mc8-c94m-mjg8?

GHSA-6mc8-c94m-mjg8 has a CVSS v3 base score of 4.3, published by GitHub Security Advisories.

GHSA-6mc8-c94m-mjg8MediumCVSS 4.3

Mattermost versions 11.9.x <= 11.9.0, 11.8.x <= 11.8.4, 11.7.x <= 11.7.8, 10.11.x <= 10.11.22...

Vendor

GitHub Security Advisories

Published

September 14, 2026

Last Modified

September 14, 2026

🔗 CVE IDs covered (1)

CVE-2026-86349 →

📋 Description

Mattermost versions 11.9.x <= 11.9.0, 11.8.x <= 11.8.4, 11.7.x <= 11.7.8, 10.11.x <= 10.11.22 fail to limit the nesting depth in the server-side Markdown parser which allows an authenticated attacker to cause a denial of service (CPU resource exhaustion) via a crafted post containing deeply nested blockquotes or list items.. Mattermost Advisory ID: MMSA-2026-00707

🔗 References (3)

https://nvd.nist.gov/vuln/detail/CVE-2026-86349
https://mattermost.com/security-updates
https://github.com/advisories/GHSA-6mc8-c94m-mjg8