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

Source: https://junglewise.ai/threats/cve-2023-41890-sustainsys-saml2-insufficient-identity-provider-issuer-validation  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2023-09-20  
License: CC BY 4.0 with a link back

CVE-2023-41890 · Severity: low · CVSS 3.1 · Published 2023-09-20

Sustainsys.Saml2 Insufficient Identity Provider Issuer Validation

Technologies: [Sustainsys.Saml2 (NuGet)](https://junglewise.ai/threats/technologies/sustainsys-saml2). Vendors: [NuGet](https://junglewise.ai/threats/vendors/nuget).

## Quick answers

**Is CVE-2023-41890 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2023-41890 being exploited in the wild.

**How severe is CVE-2023-41890?** Low severity, with a CVSS score of 3.1, published 20 September 2023.

**Which products and versions are affected?** Kentor.AuthServices (NuGet) ECOSYSTEM:introduced=0,last_affected=0.23.0; Sustainsys.Saml2 (NuGet) ECOSYSTEM:introduced=0,fixed=1.0.3.

**Is there a fix for CVE-2023-41890?** Yes. Sustainsys.Saml2 (NuGet): upgrade to 1.0.3 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2023-41890?** Check whether you run Kentor.AuthServices (NuGet) or Sustainsys.Saml2 (NuGet) 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.

## How to fix

- Sustainsys.Saml2 (NuGet): upgrade to 1.0.3 or later

  ```sh
  dotnet add package Sustainsys.Saml2 --version 1.0.3
  ```


## Affected products

- Kentor.AuthServices (NuGet) ECOSYSTEM:introduced=0,last_affected=0.23.0
- Sustainsys.Saml2 (NuGet) ECOSYSTEM:introduced=0,fixed=1.0.3

## Identifiers

- CVE-2023-41890
- GHSA-fv2h-753j-9g39

## Related threats

- [Subject Confirmation Method not validated in Saml2 Authentication Services for ASP.NET](https://junglewise.ai/threats/cve-2020-5268-subject-confirmation-method-not-validated-in-saml2-authentication)
- [Missing Token Replay Detection in Saml2 Authentication services for ASP.NET](https://junglewise.ai/threats/cve-2020-5261-missing-token-replay-detection-in-saml2-authentication-services)