CVE-2026-42849

Name: CVE-2026-42849
Creator: NVD / NIST
Published: 2026-06-02T21:16:27.67+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.3/10EPSS 0.32%

Last modified Jun 17, 2026

CVE-2026-42849 is a critical-severity vulnerability rated 9.3/10 on the CVSS scale. 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. EPSS estimates a 0.32% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1

9.3/10

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

EPSS Probability

0.32%

23.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions
Goauthentik	Authentik	< 2025.12.5
Goauthentik	Authentik	>= 2026.2.0, < 2026.2.3

References

https://github.com/goauthentik/authentik/security/advisories/GHSA-pgff-5mx8-fqj3Vendor Advisory

Timeline

Published: Jun 2, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-42849?

How severe is CVE-2026-42849?

CVE-2026-42849 has a CVSS score of 9.3/10 (CRITICAL severity). The EPSS model estimates a 0.32% probability of exploitation in the next 30 days.

How do I fix CVE-2026-42849?

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-2026-42849?

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

Scan your code now

Source: NVD / NIST