Improper Verification of Cryptographic Signature Affecting python-pysaml2 package, versions <6.1.0-0ubuntu2


Severity

Recommended
0.0
medium
0
10

Based on Ubuntu security rating.

Threat Intelligence

EPSS
0.28% (69th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-UBUNTU2204-PYTHONPYSAML2-2776834
  • published27 Feb 2021
  • disclosed21 Jan 2021

Introduced: 21 Jan 2021

CVE-2021-21239  (opens in a new tab)
CWE-347  (opens in a new tab)

How to fix?

Upgrade Ubuntu:22.04 python-pysaml2 to version 6.1.0-0ubuntu2 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream python-pysaml2 package and not the python-pysaml2 package as distributed by Ubuntu. See How to fix? for Ubuntu:22.04 relevant fixed versions and status.

PySAML2 is a pure python implementation of SAML Version 2 Standard. PySAML2 before 6.5.0 has an improper verification of cryptographic signature vulnerability. Users of pysaml2 that use the default CryptoBackendXmlSec1 backend and need to verify signed SAML documents are impacted. PySAML2 does not ensure that a signed SAML document is correctly signed. The default CryptoBackendXmlSec1 backend is using the xmlsec1 binary to verify the signature of signed SAML documents, but by default xmlsec1 accepts any type of key found within the given document. xmlsec1 needs to be configured explicitly to only use only x509 certificates for the verification process of the SAML document signature. This is fixed in PySAML2 6.5.0.

CVSS Scores

version 3.1