Vulnerability in Casdoor

CVE-2026-9098

In Casdoor versions 2.362.0 and earlier, the SAML callback handler in controllers/auth.go accepts any well-formed SAMLResponse sent to /api/acs without verifying that it corresponds to an AuthnRequest previously issued by Casdoor. Additionally, if an administrator disables or deletes an IdP (Identity Provider) after a SAML flow has started, the handler still processes the response using the provider snapshot loaded at the start of the request. As a result, an attacker controlling a registered upstream IdP can send unsolicited SAML responses, or replay a legitimately captured response in a different session or after the original flow has ended. In both cases, Casdoor accepts the response and issues a session, enabling persistent unauthorized access.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.002 (10.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 11th percentile — 10.6% 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-2026-9098: held from 0.002 to 0.002.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: -0.000

Affected products

References

Frequently asked questions

What is CVE-2026-9098?
CVE-2026-9098 is a critical-severity vulnerability in Casdoor, classified under CWE-346 ORIGIN VALIDATION ERROR. CVSS score: 9.1/10. Published 2026-05-28.
How severe is CVE-2026-9098?
Critical severity. CVSS v3 base score is 9.1 out of 10.