VulnerabilityAwaiting classification

CVE-2026-9090

CRITICAL · 9.1 CVSS v3.1 Published 2026-05-28
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Casdoor versions 2.362.0 and earlier contain an authentication bypass in SAML authentication. The buildSpCertificateStore function extracts the X.509 certificate from the incoming SAMLResponse instead of validating against pre-configured trusted Identity Provider certificates, allowing attackers to sign forged SAML assertions with attacker-controlled keys.

MitigationUpdate Casdoor to a version newer than 2.362.0 that implements proper certificate validation against trusted IdP configuration rather than accepting certificates from the SAMLResponse.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify Casdoor installation and version
    Locate the Casdoor binary or container image and retrieve its version (e.g., run 'casdoor --version', check docker image tag, or inspect the binary metadata)
    Affected if Version is 2.362.0 or earlier
  2. Determine if SAML authentication is configured
    Search for SAML IdP configuration files or database records containing SAML provider settings (look for fields like 'issuer', 'idpMetadataUrl', or 'samlEndpoint')
    Affected if SAML authentication is enabled with at least one external Identity Provider configured
  3. Verify SAML certificate validation behavior
    Inspect the buildSpCertificateStore function source code or runtime behavior to confirm whether it accepts certificates directly from incoming SAMLResponse rather than validating against pre-configured trusted IdP certificates
    Affected if The function extracts and trusts certificates from SAMLResponse instead of using pre-configured trusted IdP certificates
  4. Check for unauthorized SAML trust relationships
    Review SAML IdP configurations to identify any IdPs with certificates that were not explicitly configured by administrators
    Affected if Any SAML IdP configuration contains certificates that were not explicitly provisioned by the administrator prior to the authentication attempt

A user is affected if running Casdoor version 2.362.0 or earlier with SAML authentication configured, as the system accepts attacker-supplied certificates from SAML responses instead of validating against trusted IdP certificates.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Update Casdoor to a version newer than 2.362.0 that implements proper certificate validation against trusted IdP configuration rather than accepting certificates from the SAMLResponse.

Have this fixed Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing8.0 h
  • Review / QA4.0 h
24.0 hours of engineering $4,160
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-9090 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data