What is GHSA-vr3j-2q9w-h26r?

GHSA-vr3j-2q9w-h26r is a security advisory published by GitHub Security Advisories with Medium severity. Mattermost Plugins versions \u003c=11.8 10.20.11 11.5.7.0 _The Mattermost GitLab plugin fails to...

Which CVE IDs does GHSA-vr3j-2q9w-h26r cover?

GHSA-vr3j-2q9w-h26r covers the following CVE IDs: CVE-2026-16049. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

What is the CVSS v3 score of GHSA-vr3j-2q9w-h26r?

GHSA-vr3j-2q9w-h26r has a CVSS v3 base score of 4.3, published by GitHub Security Advisories.

GHSA-vr3j-2q9w-h26rMediumCVSS 4.3

Mattermost Plugins versions <=11.8 10.20.11 11.5.7.0 _The Mattermost GitLab plugin fails to...

Vendor

GitHub Security Advisories

Published

August 17, 2026

Last Modified

August 17, 2026

🔗 CVE IDs covered (1)

CVE-2026-16049 →

📋 Description

Mattermost Plugins versions <=11.8 10.20.11 11.5.7.0 The Mattermost GitLab plugin fails to verify channel permissions when processing API requests with a caller-supplied {{post_id}}, and fails to validate the {{web_url}} parameter against the configured GitLab instance, which allows an authenticated attacker to inject bot-authored messages containing arbitrary URLs into channels they do not have access to via the {{createIssue}} and {{attachCommentToIssue}} API endpoints. Mattermost Advisory ID: MMSA-2026-00673

🔗 References (3)

https://nvd.nist.gov/vuln/detail/CVE-2026-16049
https://mattermost.com/security-updates
https://github.com/advisories/GHSA-vr3j-2q9w-h26r