CVE-2021-21238

SAML XML Signature wrapping

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.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.14%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory pypi.org
Affected: IdentityPython pysaml2
Published at:
Updated at:

References

Link Tags
https://pypi.org/project/pysaml2 third party advisory product
https://github.com/IdentityPython/pysaml2/releases/tag/v6.5.0 third party advisory
https://github.com/IdentityPython/pysaml2/security/advisories/GHSA-f4g9-h89h-jgv9 third party advisory
https://github.com/IdentityPython/pysaml2/commit/1d8fd268f5bf887480a403a7a5ef8f048157cc14 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-21238?
CVE-2021-21238 has been scored as a medium severity vulnerability.
How to fix CVE-2021-21238?
To fix CVE-2021-21238, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-21238 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-21238 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-21238?
CVE-2021-21238 affects IdentityPython pysaml2.
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