CVE-2020-5268 (GCVE-0-2020-5268)

Vulnerability from cvelistv5 – Published: 2020-04-21 15:30 – Updated: 2024-08-04 08:22
VLAI
Title
Subject Confirmation Method not validated in Saml2 Authentication Services for ASP.NET
Summary
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.
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:L/A:N
CWE
  • CWE-303 - Incorrect Implementation of Authentication Algorithm
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7771 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Sustainsys Saml2 Affected: < 1.0.2
Affected: >= 2.0.0, <= 2.6.0
guessed Create a notification for this product.
Show details on NVD website
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