CVE-2026-42849 json
authentik: Reflected XSS in SFE AutosubmitStage allows IDP account takeover
published 5mo ago modified 2mo ago also BIT-authentik-2026-42849 , EUVD-2026-34026 , GHSA-pgff-5mx8-fqj3
- cvss
- 9.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 25%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- bitnami authentik 2025.12.5, 2026.2.3
- goauthentik authentik 2025.12.5, 2026.2.3
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 5mo ago
Exploit prediction
0.33% chance of exploitation in the next 30 days, higher than 25% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 9.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N |
| OSV | 3.1 | 9.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| bitnami | authentik | <2025.12.5 >=2026.0.0, <2026.2.3 |
2025.12.5 2026.2.3 |
Affected products
- goauthentik authentik
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/goauthentik/authentik/security/advisories/GHSA-pgff-5mx8-fqj3
vendor-advisory, advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-42849
web
Sources
- CVE List CVE-2026-42849
- NVD CVE-2026-42849
- OSV BIT-authentik-2026-42849
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.