Open Redirect in Mattermost
CVE-2025-9072
Mattermost versions 10.10.x <= 10.10.1, 10.5.x <= 10.5.9, 10.9.x <= 10.9.4 fail to validate the redirect_to parameter, allowing an attacker to craft a malicious link that, once a user authenticates with their SAML provider, could post the user’s cookies to an attacker-controlled URL.
Vulnerability class: Open Redirect
EPSS: 0.002 (5.7th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.6 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:L.
Affected products
- Mattermost — versions 10.10.0, 10.5.0, 10.9.0
- Mattermost Mattermost_server
Weakness classification (CWE)
Public proof-of-concept exploits
References
- responsibledisclosure@mattermost.com (Vendor Advisory)
Frequently asked questions
- What is CVE-2025-9072?
- CVE-2025-9072 is a high-severity vulnerability in Mattermost, classified under URL Redirection to Untrusted Site (Open Redirect). CVSS score: 7.6/10. Published 2025-09-15.
- How severe is CVE-2025-9072?
- High severity. CVSS v3 base score is 7.6 out of 10.
- Is CVE-2025-9072 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.