CVE-2026-47201

HIGH

authentik: XML Signature Wrapping in SAML Source ACS allows authentication as arbitrary federated user

Title source: cna
STIX 2.1

Description

authentik is an open-source identity provider. Prior to versions 2025.12.5, 2026.2.3, and 2026.5.1, authentik's SAML Source ACS endpoint is vulnerable to XML Signature Wrapping when validating upstream SAML responses. An attacker with any account at the upstream IdP can reuse a valid signed assertion to authenticate as another federated user. This issue has been patched in versions 2025.12.5, 2026.2.3, and 2026.5.1.

References (1)

Core 1
Core References

Scores

CVSS v3 8.5
EPSS 0.0025
EPSS Percentile 16.2%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact total

Details

CWE
CWE-20 CWE-347
Status published
Products (5)
Go/goauthentik.io 0 - 0.0.0-20260528144335-a370d76d23c7Go
goauthentik/authentik < 2025.12.6
goauthentik/authentik < 2025.12.5
goauthentik/authentik < 2026.2.3
goauthentik/authentik < 2026.5.1
Published Jun 02, 2026
Tracked Since Jun 03, 2026