vulnerability
Ubuntu: (CVE-2021-21238): python-pysaml2 vulnerability
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 4 | (AV:N/AC:M/Au:N/C:N/I:P/A:N) | Jan 21, 2021 | Jun 26, 2025 | Mar 27, 2026 |
Severity
4
CVSS
(AV:N/AC:M/Au:N/C:N/I:P/A:N)
Published
Jan 21, 2021
Added
Jun 26, 2025
Modified
Mar 27, 2026
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.
Solution
no-fix-ubuntu-package
References
- CVE-2021-21238
- https://attackerkb.com/topics/CVE-2021-21238
- CWE-347
- EUVD-EUVD-2021-0210
- https://euvd.enisa.europa.eu/vulnerability/EUVD-2021-0210
- https://github.com/IdentityPython/pysaml2/releases/tag/v6.5.0
- https://github.com/IdentityPython/pysaml2/security/advisories/GHSA-f4g9-h89h-jgv9
- https://pypi.org/project/pysaml2
- https://www.cve.org/CVERecord?id=CVE-2021-21238
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