Open Redirect in Simplesamlphp Simplesamlphp-Casserver

CVE-2025-65954

SimpleSAMLphp-casserver is a CAS 1.0 and 2.0 compliant CAS server in the form of a SimpleSAMLphp module. In versions below 6.3.1 and 7.0.0, the logout endpoint accepts a url query parameter to redirect to. casserver treats that url as trusted, and either (depending on configuration) redirects the browser there, or shows a "you've been logged out" page with a link to continue to that url. Impacted configs include 'enable_logout' => true, and 'skip_logout_page' -> true. This issue has been resolved in versions 6.3.1 and 7.0.0.

Vulnerability class: Open Redirect

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (17.1th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 17th percentile — 17.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-65954: held from 0.003 to 0.003.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-65954?
CVE-2025-65954 is a medium-severity vulnerability in Simplesamlphp Simplesamlphp-Casserver, classified under URL Redirection to Untrusted Site (Open Redirect). CVSS score: 6.1/10. Published 2026-05-18.
How severe is CVE-2025-65954?
Medium severity. CVSS v3 base score is 6.1 out of 10.