CVE-2020-27847

dexidp/dex: authentication bypass in saml authentication

Published 28 May 2021Modified 17 Jun 2026CWE 228

In the Trivy database since at least 24 Oct 2026, 07:11 UTCWhen it arrived before that build is not recorded.

Severity by source

NVD9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

GHSA9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Red Hat9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Trivy's own label is CRITICAL. Rated critical by NVD, GHSA, Red Hat.

Description

A vulnerability exists in the SAML connector of the github.com/dexidp/dex library used to process SAML Signature Validation. This flaw allows an attacker to bypass SAML authentication. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability. This flaw affects dex versions before 2.27.0.

Affected packages and fixed versions

Source	Package	Fixed in
go::GitHub Security Advisory Go	github.com/dexidp/dex	2.27.0
chainguard	kots	0
rapidfort alpine 3.20	dex	no fix listed
rapidfort alpine 3.21	dex	no fix listed
rapidfort alpine 3.22	dex	no fix listed
rapidfort alpine 3.23	dex	no fix listed
rapidfort alpine 3.24	dex	no fix listed
wolfi	kots	0

References

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RecordsEach decision is recorded with the policy that ran and its hash, then sealed under a signed checkpoint.

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Vulnerability data compiled from the Trivy vulnerability database (trivy-db, Aqua Security, Apache License 2.0), which aggregates third-party advisories. CVE records are published by The MITRE Corporation under the CVE Terms of Use; CVE is a trademark of MITRE. This product uses data from the NVD API but is not endorsed or certified by the NVD. Severity, titles and advisory data from the GitHub Advisory Database (CC BY 4.0), Red Hat security data (CC BY 4.0) and the other sources linked on each entry. Entries may be summarised or re-formatted; the linked original is the authoritative record.