How severe is CVE-2026-9090?

CVE-2026-9090 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2026-9090 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-9090?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2026-9090 have an EU (EUVD) identifier?

Yes. CVE-2026-9090 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-32941.

When was CVE-2026-9090 published?

CVE-2026-9090 was published on 2026-05-28 and last updated on 2026-06-17.

CVE-2026-9090

CVE-2026-9090 is a critical-severity vulnerability with a CVSS 3.x base score of 9.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
EPSS exploit prediction: 0% (10th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-32941
Published: 2026-05-28
Last modified: 2026-06-17

Description

Casdoor versions 2.362.0 and earlier contain a vulnerability that allows an attacker to bypass authentication by supplying an arbitrary signing certificate. The buildSpCertificateStore function extracts the X.509 certificate directly from the incoming SAMLResponse instead of using the trusted pre-configured Identity Provider certificate, allowing an attacker to forge assertions signed with an attacker-controlled key.

Frequently asked questions

What is CVE-2026-9090?: Casdoor versions 2.362.0 and earlier contain a vulnerability that allows an attacker to bypass authentication by supplying an arbitrary signing certificate. The buildSpCertificateStore function extracts the X.509 certificate directly from the incoming SAMLResponse instead of using the trusted pre-configured Identity Provider certificate, allowing an attacker to forge assertions signed with an attacker-controlled key.
How severe is CVE-2026-9090?: CVE-2026-9090 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2026-9090 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-9090?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-9090 have an EU (EUVD) identifier?: Yes. CVE-2026-9090 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-32941.
When was CVE-2026-9090 published?: CVE-2026-9090 was published on 2026-05-28 and last updated on 2026-06-17.

References

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