What is GHSA-c8hv-77r5-h5f7?

GHSA-c8hv-77r5-h5f7 is a security advisory published by GitHub Security Advisories with Medium severity. Mattermost versions 11.7.x \u003c= 11.7.2, 11.6.x \u003c= 11.6.4, 10.11.x \u003c= 10.11.19 fail to validate the...

Which CVE IDs does GHSA-c8hv-77r5-h5f7 cover?

GHSA-c8hv-77r5-h5f7 covers the following CVE IDs: CVE-2026-6850. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

What is the CVSS v3 score of GHSA-c8hv-77r5-h5f7?

GHSA-c8hv-77r5-h5f7 has a CVSS v3 base score of 6.5, published by GitHub Security Advisories.

GHSA-c8hv-77r5-h5f7MediumCVSS 6.5

Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to validate the...

Vendor

GitHub Security Advisories

Published

July 13, 2026

Last Modified

July 13, 2026

🔗 CVE IDs covered (1)

CVE-2026-6850 →

📋 Description

Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to validate the length and content of message attachment field values, which allows an authenticated attacker to cause a denial of service for all users in a channel via a post containing a specially crafted payload that triggers catastrophic backtracking in the client-side markdown parser.. Mattermost Advisory ID: MMSA-2026-00658

🔗 References (3)

https://nvd.nist.gov/vuln/detail/CVE-2026-6850
https://mattermost.com/security-updates
https://github.com/advisories/GHSA-c8hv-77r5-h5f7