# CVE-2026-9098: Casdoor SAML response validation bypass in auth controller

Source: https://junglewise.ai/threats/cve-2026-9098-casdoor-saml-response-validation-bypass-in-auth-controller  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-28. Updated: 2026-07-02  
License: CC BY 4.0 with a link back

CVE-2026-9098 · Severity: critical · CVSS 9.1 · Published 2026-05-28

Casdoor, an identity and access management platform, contains a flaw in how it handles login requests from external identity providers. The system fails to verify that an incoming login response actually matches a request it previously sent, allowing attackers to submit unsolicited or old login data. If exploited, an attacker could gain persistent, unauthorized access to user accounts, including administrative accounts, potentially leading to a full system compromise.

Technologies: [github.com/casdoor/casdoor (Go)](https://junglewise.ai/threats/technologies/github-com-casdoor-casdoor). Vendors: [Go](https://junglewise.ai/threats/vendors/go).

## Quick answers

**Is CVE-2026-9098 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-9098 being exploited in the wild.

**How severe is CVE-2026-9098?** Critical severity, with a CVSS score of 9.1, published 28 May 2026.

**Which products and versions are affected?** github.com/casdoor/casdoor (Go) <= 1.1000.1-0.20260321120606-239e8bd69487, SEMVER:introduced=0, SEMVER:introduced=0,last_affected=1.1000.1-0.20260321120606-239e8bd69487.

**Is there a fix for CVE-2026-9098?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-9098 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-9098?** Check whether you run github.com/casdoor/casdoor (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A vulnerability exists in the SAML callback handler within `controllers/auth.go` of Casdoor. The `/api/acs` endpoint accepts any well-formed `SAMLResponse` without verifying its correlation to a previously issued `AuthnRequest`. Furthermore, the handler uses a provider snapshot loaded at the start of a request, meaning it may process responses for Identity Providers (IdPs) that were disabled or deleted mid-flow. An attacker controlling a registered upstream IdP can exploit this to send unsolicited responses or replay captured responses to obtain authenticated sessions. As of the advisory date, no patch is available.

## Affected products

- Casdoor Casdoor <= 2.362.0

## Identifiers

- CVE-2026-9098
- GHSA-mfvp-7p3v-x9mh
- GO-2026-5898

## Timeline

- 2026-05-28: advisory: Initial disclosure by CERT/CC and GitHub Advisory Database
- 2026-05-28: disclosed

## References

- [https://kb.cert.org/vuls/id/780781](https://kb.cert.org/vuls/id/780781)

## Related threats

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- [Casdoor MFA bypass in social-login binding flow](https://junglewise.ai/threats/cve-2026-9091-casdoor-mfa-bypass-in-social-login-binding-flow)