Vulnerability Name:

CVE-2021-21239 (CCN-195402)

Assigned:2020-12-22
Published:2021-01-20
Updated:2021-03-10
Summary: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.
CVSS v3 Severity:6.5 Medium (CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N)
5.7 Medium (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): Required
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): None
Integrity (I): High
Availibility (A): None
6.5 Medium (CCN CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N)
5.7 Medium (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): Required
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): None
Integrity (I): High
Availibility (A): None
CVSS v2 Severity:4.3 Medium (CVSS v2 Vector: AV:N/AC:M/Au:N/C:N/I:P/A:N)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Medium
Authentication (Au): None
Impact Metrics:Confidentiality (C): None
Integrity (I): Partial
Availibility (A): None
6.8 Medium (CCN CVSS v2 Vector: AV:N/AC:L/Au:S/C:N/I:C/A:N)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Athentication (Au): Single_Instance
Impact Metrics:Confidentiality (C): None
Integrity (I): Complete
Availibility (A): None
Vulnerability Type:CWE-347
Vulnerability Consequences:Bypass Security
References:Source: MITRE
Type: CNA
CVE-2021-21239

Source: XF
Type: UNKNOWN
pysaml2-cve202121239-sec-bypass(195402)

Source: MISC
Type: Patch, Third Party Advisory
https://github.com/IdentityPython/pysaml2/commit/46578df0695269a16f1c94171f1429873f90ed99

Source: MISC
Type: Third Party Advisory
https://github.com/IdentityPython/pysaml2/releases/tag/v6.5.0

Source: CCN
Type: PySAML2 GIT Repository
Unspecified xmlsec1 key-type preference

Source: CONFIRM
Type: Third Party Advisory
https://github.com/IdentityPython/pysaml2/security/advisories/GHSA-5p3x-r448-pc62

Source: MLIST
Type: Mailing List, Third Party Advisory
[debian-lts-announce] 20210226 [SECURITY] [DLA 2577-1] python-pysaml2 security update

Source: MISC
Type: Product, Third Party Advisory
https://pypi.org/project/pysaml2

Source: MISC
Type: Exploit, Mailing List, Third Party Advisory
https://www.aleksey.com/pipermail/xmlsec/2013/009717.html

Source: CCN
Type: WhiteSource Vulnerability Database
CVE-2021-21239

Vulnerable Configuration:Configuration 1:
  • cpe:/a:pysaml2_project:pysaml2:*:*:*:*:*:*:*:* (Version < 6.5.0)

    • Configuration 2:
  • cpe:/o:debian:debian_linux:9.0:*:*:*:*:*:*:*

    • * Denotes that component is vulnerable
    Oval Definitions
    Definition IDClassTitleLast Modified
    oval:org.opensuse.security:def:113287
    P
    		python36-pysaml2-7.0.1-1.2 on GA media (Moderate)
    2022-01-17
    oval:org.opensuse.security:def:106699
    P
    		python36-pysaml2-7.0.1-1.2 on GA media (Moderate)
    2021-10-01
    oval:org.opensuse.security:def:84184
    P
    		Security update for ardana-cobbler, cassandra, cassandra-kit, crowbar-core, crowbar-openstack, documentation-suse-openstack-cloud, grafana, kibana, openstack-heat-templates, openstack-monasca-installer, openstack-nova, python-Django, python-elementpath, python-eventlet, python-py, python-pysaml2, python-six, python-xmlschema (Moderate)
    2021-07-28
    oval:org.opensuse.security:def:84643
    P
    		Security update for ardana-cobbler, cassandra, cassandra-kit, crowbar-core, crowbar-openstack, documentation-suse-openstack-cloud, grafana, kibana, openstack-heat-templates, openstack-monasca-installer, openstack-nova, python-Django, python-elementpath, python-eventlet, python-py, python-pysaml2, python-six, python-xmlschema (Moderate)
    2021-07-28
    oval:org.opensuse.security:def:88141
    P
    		Security update for ardana-neutron, ardana-swift, cassandra, crowbar-openstack, grafana, kibana, openstack-dashboard, openstack-ironic, openstack-neutron, openstack-neutron-gbp, openstack-nova, python-Django1, python-py, python-pysaml2, python-xmlschema, rubygem-activerecord-session_store, venv-openstack-keystone (Moderate)
    2021-06-11
    oval:org.opensuse.security:def:88454
    P
    		Security update for ardana-neutron, ardana-swift, cassandra, crowbar-openstack, grafana, kibana, openstack-dashboard, openstack-ironic, openstack-neutron, openstack-neutron-gbp, openstack-nova, python-Django1, python-py, python-pysaml2, python-xmlschema, rubygem-activerecord-session_store, venv-openstack-keystone (Moderate)
    2021-06-11
    BACK
    pysaml2_project pysaml2 *
    debian debian linux 9.0