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.

Score

CVSS 3.1 7.6 High

Status

Analyzed - responsibledisclosure@mattermost.com

Published

2025-09-15

Last modified

2026-10-19

Weaknesses

CWE-601

Affected products

• Mattermost (Mattermost)
• Mattermost Server (Mattermost)

References

• https://mattermost.com/security-updates