Is CVE-2026-9090 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-9090 being exploited in the wild.

How severe is CVE-2026-9090?

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-2026-9090?

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-2026-9090 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-9090?

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.

CVE-2026-9090: Casdoor SAML authentication bypass via arbitrary signing certificate

Q: Is there a fix for CVE-2026-9090?

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.

Q: How is CVE-2026-9090 attacked?

It is attacked over the network, in a software library.

Q: Am I affected by CVE-2026-9090?

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.

CVE-2026-9090 · Severity: critical · CVSS 9.1 · Published 2026-05-28

Casdoor, an open-source identity and access management platform, contains a critical security flaw in how it handles login requests. An attacker can bypass the authentication process by providing a fake security certificate, allowing them to log in as any user, including administrators, without a password. This could lead to a total compromise of the identity system and unauthorized access to all connected applications and customer data.

Technologies: github.com/casdoor/casdoor (Go). Vendors: Go.

Quick answers

Is CVE-2026-9090 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-9090 being exploited in the wild.
How severe is CVE-2026-9090?: 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-2026-9090?: 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-2026-9090 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-9090?: 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

An authentication bypass vulnerability exists in Casdoor's SAML service provider implementation. The 'buildSpCertificateStore' function improperly extracts X.509 certificates directly from incoming SAMLResponse messages rather than validating them against a pre-configured, trusted Identity Provider (IdP) certificate. A remote, unauthenticated attacker can exploit this by crafting a SAML assertion signed with an arbitrary, attacker-controlled key. Successful exploitation allows the attacker to impersonate any user subject within the system. As of the advisory date, no official patch is available.

Affected products

Casdoor Casdoor <= 2.362.0

Identifiers

CVE-2026-9090
GHSA-fwgq-j9r9-qjgr
GO-2026-5895

Timeline

2026-05-28: advisory: Original release date of VU#780781 and GHSA-fwgq-j9r9-qjgr
2026-05-28: disclosed: CVE-2026-9090 published

References

https://kb.cert.org/vuls/id/780781

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