Open Redirect in Mattermost

CVE-2025-9084

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

Vulnerability class: Open Redirect

EPSS: 0.002 (5.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 3.1 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-9084?
CVE-2025-9084 is a low-severity vulnerability in Mattermost, classified under URL Redirection to Untrusted Site (Open Redirect). CVSS score: 3.1/10. Published 2025-09-15.
How severe is CVE-2025-9084?
Low severity. CVSS v3 base score is 3.1 out of 10.
Is CVE-2025-9084 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.