by Kastro
Paper/Archive/CVE-2026-42849

CVE-2026-42849

goauthentik authentik — authentik: Reflected XSS in SFE AutosubmitStage allows IDP account takeover

EPSS 0.3%CVSS 9.3
critical.is priorityof 100
33
CVSS 9.3 (CNA)9.3 / 10 × 3027.9Not in CISA KEV+300.0EPSS percentile 25.8.258 × 205.2No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
authentik< 2025.12.5–CNA
authentik< 2026.2.3–CNA

Scores by source

GitHub_M (CNA)9.3CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N
CISA ADPSSVCExploitation: none · Automatable: no · Technical impact: partial

References

refgithub.com/goauthentik/authentik/security/advisories/GHSA-pgff-5mx8-fqj3