6.5 Medium
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
HIGH
Availability Impact
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
4.3 Medium
CVSS2
Access Vector
NETWORK
Access Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
PARTIAL
Availability Impact
NONE
AV:N/AC:M/Au:N/C:N/I:P/A:N
0.002 Low
EPSS
Percentile
57.5%
All users of pysaml2 that use the default CryptoBackendXmlSec1
backend and need to verify signed SAML documents are impacted. pysaml2 <= 6.4.1
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.
Users should upgrade to pysaml2 v6.5.0
.
No workaround provided at this point.
This issue has been reported in the past at the xmlsec1 mailing list:
https://www.aleksey.com/pipermail/xmlsec/2013/009717.html
If you have any questions or comments about this advisory:
github.com/IdentityPython/pysaml2
github.com/IdentityPython/pysaml2/commit/46578df0695269a16f1c94171f1429873f90ed99
github.com/IdentityPython/pysaml2/releases/tag/v6.5.0
github.com/IdentityPython/pysaml2/security/advisories/GHSA-5p3x-r448-pc62
lists.debian.org/debian-lts-announce/2021/02/msg00038.html
nvd.nist.gov/vuln/detail/CVE-2021-21239
pypi.org/project/pysaml2
www.aleksey.com/pipermail/xmlsec/2013/009717.html
6.5 Medium
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
HIGH
Availability Impact
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
4.3 Medium
CVSS2
Access Vector
NETWORK
Access Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
PARTIAL
Availability Impact
NONE
AV:N/AC:M/Au:N/C:N/I:P/A:N
0.002 Low
EPSS
Percentile
57.5%