CVE-2021-21238

SAML XML Signature wrapping

Severity Score

6.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

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.

PySAML2 es una implementación de Python pura de SAML Versión 2 Estándar. PySAML2 versiones anteriores a 6.5.0, presenta una verificación inapropiada de una vulnerabilidad de firma criptográfica. Todos los usuarios de pysaml2 que necesitan comprobar documentos SAML firmados están afectados. La vulnerabilidad es una variante del empaquetado de firma XML porque no validó el documento SAML con un esquema XML. Esto permitió que documentos XML sean procesados no válidos y dicho documento puede engañar a pysaml2 con una firma empaquetada. Esto es corregido en PySAML2 versión 6.5.0

*Credits: N/A

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

None

Integrity

High

Availability

None

Attack Vector

Network

Attack Complexity

Medium

Authentication

None

Confidentiality

None

Integrity

Partial

Availability

None

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2020-12-22 CVE Reserved
2021-01-21 CVE Published
2024-08-03 CVE Updated
2024-11-10 EPSS Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-347: Improper Verification of Cryptographic Signature

CAPEC

References (4)

URL	Tag	Source
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://pypi.org/project/pysaml2	Product

URL	Date	SRC

URL	Date	SRC
https://github.com/IdentityPython/pysaml2/commit/1d8fd268f5bf887480a403a7a5ef8f048157cc14	2021-01-29

URL	Date	SRC

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Pysaml2 Project Search vendor "Pysaml2 Project"		Pysaml2 Search vendor "Pysaml2 Project" for product "Pysaml2"				< 6.5.0 Search vendor "Pysaml2 Project" for product "Pysaml2" and version " < 6.5.0"		-		Affected