CVE-2025-9084: Mattermost Open Redirect vulnerability

September 15, 2025 (updated September 16, 2025)

Mattermost versions 10.5.x <= 10.5.9 fail to properly validate redirect URLs which allows attackers to redirect users to malicious sites via crafted OAuth login URLs.

References

github.com/advisories/GHSA-hm95-jx66-g2gh
github.com/mattermost/mattermost
github.com/mattermost/mattermost/commit/39bd251fe4f66b7e847fc6d653221886347ff160
mattermost.com/security-updates
nvd.nist.gov/vuln/detail/CVE-2025-9084

Code Behaviors & Features

Detect and mitigate CVE-2025-9084 with GitLab Dependency Scanning

Secure your software supply chain by verifying that all open source dependencies used in your projects contain no disclosed vulnerabilities. Learn more about Dependency Scanning →