7.5
CWE
289 294
Advisory Published
Advisory Published
Updated

CVE-2023-41890: Sustainsys.Saml2 Insufficient Identity Provider Issuer Validation

First published: Tue Sep 19 2023(Updated: )

### Impact When a response is processed, the issuer of the Identity Provider is not sufficiently validated. This could allow a malicious identity provider to craft a Saml2 response that is processed as if issued by another identity provider. It is also possible for a malicious end user to cause stored state intended for one identity provider to be used when processing the response from another provider. An application is impacted if they rely on any of these features in their authentication/authorization logic: * the issuer of the generated identity and claims * items in the stored request state (AuthenticationProperties) ### Patches Patched in version 2.9.2 and 1.0.3. All previous versions are vulnerable. ### Workarounds The `AcsCommandResultCreated` notification can be used to add the validation required if an upgrade to patched packages is not possible. ### References The patch is linked to https://github.com/Sustainsys/Saml2/issues/712 and https://github.com/Sustainsys/Saml2/issues/713

Credit: security-advisories@github.com security-advisories@github.com security-advisories@github.com

Affected SoftwareAffected VersionHow to fix
nuget/Kentor.AuthServices<=0.23.0
nuget/Sustainsys.Saml2>=2.0.0<2.9.2
2.9.2
nuget/Sustainsys.Saml2<1.0.3
1.0.3
Sustainsys Saml2<1.0.3
Sustainsys Saml2>=2.0.0<2.9.2
SimpleSAMLphp<1.0.3
SimpleSAMLphp>=2.0.0<2.9.2

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Frequently Asked Questions

  • What is CVE-2023-41890?

    CVE-2023-41890 is a vulnerability in the Sustainsys.Saml2 library that allows a malicious identity provider to craft a Saml2 response that is processed as if issued by another identity provider.

  • How does CVE-2023-41890 impact ASP.NET web sites?

    CVE-2023-41890 allows a malicious identity provider or end user to exploit the vulnerability, potentially leading to unauthorized access or impersonation.

  • What is the severity of CVE-2023-41890?

    CVE-2023-41890 has a severity rating of 7.5 (high).

  • How can I fix CVE-2023-41890 in my ASP.NET web site?

    To fix CVE-2023-41890, update the Sustainsys.Saml2 library to version 2.9.2 or apply the appropriate remedy provided by Sustainsys.

  • Where can I find more information about CVE-2023-41890?

    You can find more information about CVE-2023-41890 on the official GitHub page of Sustainsys.Saml2 library.

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