CVE-2026-42849 CRITICAL

CVE-2026-42849: authentik: Reflected XSS in SFE AutosubmitStage allows IDP account takeover

Vendor Goauthentik
Product authentik
Weakness CWE-79 · XSS
Published June 2, 2026
Last update June 3, 2026
View on NVD All CVEs

CVSS base score

9.3/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction Required
Confidentiality High
Integrity High

CVSS vector

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

What the vulnerability does

01Description

authentik is an open-source identity provider. Prior to versions 2025.12.5 and 2026.2.3, due to the implementation of stages in the SFE (Simple Flow Executor) in order to make the interface more compatible with legacy browsers, it was possible to use an XSS exploit in the AutosubmitStage. This issue has been patched in versions 2025.12.5 and 2026.2.3.

Key dates

02Disclosure timeline

June 2, 2026 CVE published
June 3, 2026 Record updated