Is CVE-2026-42849 in the CISA KEV catalog?

No. CVE-2026-42849 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2026-42849?

CVE-2026-42849 has a CVSS v3 base score of 9.3 (CRITICAL).

What is the EPSS score for CVE-2026-42849?

CVE-2026-42849 has an EPSS score of 0.32% (23th percentile), estimating the probability of exploitation in the next 30 days.

CVE & CISA-KEV Catalog

CVE-2026-42849

CRITICAL

9.3

CVSS v3

NVD

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.

CWE-79Cross-Site Scripting (XSS)

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionRequired

ScopeChanged

Impact

ConfidentialityHigh

IntegrityHigh

AvailabilityNone

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

Exploit Intelligence

0.32%probability of exploitation in 30 days

23rdpercentile

Low risk: more likely to be exploited than 23% of all known CVEs.

References

https://github.com/goauthentik/authentik/security/advisories/GHSA-pgff-5mx8-fqj3

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-06-04.