VULNERABILITY INTELLIGENCE

CVE-2021-21238

CVSS score6.5 MEDIUM
EPSS probability1.10%
CISA KEVNot currently listed
Published2021-01-21
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

Description

PySAML2 is a pure python implementation of SAML Version 2 Standard. PySAML2 before 6.5.0 has an improper verification of cryptographic signature vulnerability. All users of pysaml2 that need to validate signed SAML documents are impacted. The vulnerability is a variant of XML Signature wrapping because it did not validate the SAML document against an XML schema. This allowed invalid XML documents to be processed and such a document can trick pysaml2 with a wrapped signature. This is fixed in PySAML2 6.5.0.

Weakness classification

  • security-advisories@github.com: CWE-347

Primary references