CVE-2020-5268

Vulnerability Description

In Saml2 Authentication Services for ASP.NET versions before 1.0.2, and between 2.0.0 and 2.6.0, there is a vulnerability in how tokens are validated in some cases. Saml2 tokens are usually used as bearer tokens - a caller that presents a token is assumed to be the subject of the token. There is also support in the Saml2 protocol for issuing tokens that is tied to a subject through other means, e.g. holder-of-key where possession of a private key must be proved. The Sustainsys.Saml2 library incorrectly treats all incoming tokens as bearer tokens, even though they have another subject confirmation method specified. This could be used by an attacker that could get access to Saml2 tokens with another subject confirmation method than bearer. The attacker could then use such a token to create a log in session. This vulnerability is patched in versions 1.0.2 and 2.7.0.

CVSS Score

Affected Products

Related Weaknesses (CWE)

References

• https://github.com/Sustainsys/Saml2/commit/e58e0a1aff2b1ead6aca080b7cdced55ee6d5PatchThird Party Advisory
• https://github.com/Sustainsys/Saml2/issues/712Third Party Advisory
• https://github.com/Sustainsys/Saml2/security/advisories/GHSA-9475-xg6m-j7pwMitigationThird Party Advisory
• https://www.nuget.org/packages/Sustainsys.Saml2/Third Party Advisory
• https://github.com/Sustainsys/Saml2/commit/e58e0a1aff2b1ead6aca080b7cdced55ee6d5PatchThird Party Advisory
• https://github.com/Sustainsys/Saml2/issues/712Third Party Advisory
• https://github.com/Sustainsys/Saml2/security/advisories/GHSA-9475-xg6m-j7pwMitigationThird Party Advisory
• https://www.nuget.org/packages/Sustainsys.Saml2/Third Party Advisory