SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2020-5390

PySAML2 before 5.0.0 does not check that the signature in a SAML document is enveloped and thus signature wrapping is effective, i.e., it is affected by XML Signature Wrapping (XSW).

HIGH 7.5EPSS 1.22%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.22%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

PySAML2 before 5.0.0 does not check that the signature in a SAML document is enveloped and thus signature wrapping is effective, i.e., it is affected by XML Signature Wrapping (XSW). The signature information and the node/object that is signed can be in different places and thus the signature verification will succeed, but the wrong data will be used. This specifically affects the verification of assertion that have been signed.

CVSS 3.1
7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
EPSS
1.22% probability · 67th percentile
CISA KEV
Not listed
Weakness
CWE-347
Affected
pysaml2 project/pysaml2 · canonical/ubuntu linux · debian/debian linux
Source
cve@mitre.org

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.