What is GHSA-h2qv-vjc9-5g55?

GHSA-h2qv-vjc9-5g55 is a security advisory published by GitHub Security Advisories with Medium severity. Mattermost versions 11.9.x \u003c= 11.9.1, 11.8.x \u003c= 11.8.5, 11.7.x \u003c= 11.7.10, 11.10.x \u003c= 11.10.1...

Which CVE IDs does GHSA-h2qv-vjc9-5g55 cover?

GHSA-h2qv-vjc9-5g55 covers the following CVE IDs: CVE-2026-95666. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

What is the CVSS v3 score of GHSA-h2qv-vjc9-5g55?

GHSA-h2qv-vjc9-5g55 has a CVSS v3 base score of 4.3, published by GitHub Security Advisories.

GHSA-h2qv-vjc9-5g55MediumCVSS 4.3

Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1...

Vendor

GitHub Security Advisories

Published

September 22, 2026

Last Modified

September 22, 2026

🔗 CVE IDs covered (1)

CVE-2026-95666 →

📋 Description

Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 fail to limit the length of the post ID array accepted by the bulk reactions endpoint which allows an authenticated user to cause excessive database load via a crafted request to {{POST /api/v4/posts/ids/reactions}}.. Mattermost Advisory ID: MMSA-2026-00771

🔗 References (3)

https://nvd.nist.gov/vuln/detail/CVE-2026-95666
https://mattermost.com/security-updates
https://github.com/advisories/GHSA-h2qv-vjc9-5g55