CVEvulnerability
CVE-2021-21239
6.5 MEDIUM
Official page ↗
- Status
- Modified
- Published
- 2021-01-21
- Last modified
- 2026-06-17
- Assigner
- [email protected]
- CVSS 3.1 ([email protected])
- 6.5 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
- CVSS 3.1 ([email protected])
- 6.5 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
- CVSS 2.0 ([email protected])
- 4.3 MEDIUM — AV:N/AC:M/Au:N/C:N/I:P/A:N
- Weaknesses
- CWE-347
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. 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.
Affected configurations
• pysaml2 project pysaml2 (< 6.5.0)
• debian debian linux 9.0
Related
Weakness · CWE (1)
- CWE-347 Improper Verification of Cryptographic Signature weakness
References
- https://github.com/IdentityPython/pysaml2/commit/46578df0695269a16f1c94171f1429873f90ed99 Patch, Third Party Advisory
- https://github.com/IdentityPython/pysaml2/releases/tag/v6.5.0 Third Party Advisory
- https://github.com/IdentityPython/pysaml2/security/advisories/GHSA-5p3x-r448-pc62 Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2021/02/msg00038.html Mailing List, Third Party Advisory
- https://pypi.org/project/pysaml2 Product, Third Party Advisory
- https://www.aleksey.com/pipermail/xmlsec/2013/009717.html Exploit, Mailing List, Third Party Advisory
- https://github.com/IdentityPython/pysaml2/commit/46578df0695269a16f1c94171f1429873f90ed99 Patch, Third Party Advisory
- https://github.com/IdentityPython/pysaml2/releases/tag/v6.5.0 Third Party Advisory
- https://github.com/IdentityPython/pysaml2/security/advisories/GHSA-5p3x-r448-pc62 Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2021/02/msg00038.html Mailing List, Third Party Advisory
- https://pypi.org/project/pysaml2 Product, Third Party Advisory
- https://www.aleksey.com/pipermail/xmlsec/2013/009717.html Exploit, Mailing List, Third Party Advisory