CVE-2020-5390

Name: CVE-2020-5390
Creator: NVD / NIST
Published: 2020-01-13T19:15:12.413+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 1.21%

Last modified Jun 17, 2026

CVE-2020-5390 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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. EPSS estimates a 1.21% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

EPSS Probability

1.21%

64.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-347

Affected Software

Vendor	Product	Versions
Pysaml2 Project	Pysaml2	< 5.0.0
Canonical	Ubuntu Linux	16.04
Canonical	Ubuntu Linux	18.04
Canonical	Ubuntu Linux	19.04
Canonical	Ubuntu Linux	19.10
Debian	Debian Linux	8.0
Debian	Debian Linux	9.0
Debian	Debian Linux	10.0

References

https://github.com/IdentityPython/pysaml2/commit/5e9d5acbcd8ae45c4e736ac521fd2df5b1c62e25Patch, Third Party Advisory
https://github.com/IdentityPython/pysaml2/commit/f27c7e7a7010f83380566a219fd6a290a00f2b6ePatch, Third Party Advisory
https://github.com/IdentityPython/pysaml2/releasesRelease Notes, Third Party Advisory
https://github.com/IdentityPython/pysaml2/releases/tag/v5.0.0Release Notes, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2020/02/msg00025.htmlMailing List, Third Party Advisory
https://pypi.org/project/pysaml2/5.0.0/Product, Third Party Advisory
https://usn.ubuntu.com/4245-1/Third Party Advisory
https://www.debian.org/security/2020/dsa-4630Third Party Advisory
https://github.com/IdentityPython/pysaml2/commit/5e9d5acbcd8ae45c4e736ac521fd2df5b1c62e25Patch, Third Party Advisory
https://github.com/IdentityPython/pysaml2/commit/f27c7e7a7010f83380566a219fd6a290a00f2b6ePatch, Third Party Advisory
https://github.com/IdentityPython/pysaml2/releasesRelease Notes, Third Party Advisory
https://github.com/IdentityPython/pysaml2/releases/tag/v5.0.0Release Notes, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2020/02/msg00025.htmlMailing List, Third Party Advisory
https://pypi.org/project/pysaml2/5.0.0/Product, Third Party Advisory
https://usn.ubuntu.com/4245-1/Third Party Advisory
https://www.debian.org/security/2020/dsa-4630Third Party Advisory

Timeline

Published: Jan 13, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-5390?

How severe is CVE-2020-5390?

CVE-2020-5390 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 1.21% probability of exploitation in the next 30 days.

How do I fix CVE-2020-5390?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-5390?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST