What is CVE-2026-109374?

CVE-2026-109374 is a medium-severity vulnerability in Zitadel, classified under Incorrect Authorization. CVSS score: 5.5/10. Published 2026-10-12.

How severe is CVE-2026-109374?

Medium severity. CVSS v3 base score is 5.5 out of 10.

Auth bypass in Zitadel

CVE-2026-109374

ZITADEL 3.0.0 before 4.19.2 contains a privilege escalation vulnerability in OIDC token exchange that allows end-user impersonators to impersonate administrators including IAM_OWNER by bypassing the admin.impersonation check. Attackers holding IAM_END_USER_IMPERSONATOR or ORG_END_USER_IMPERSONATOR roles can sign in to relying applications as administrators with their roles and claims.

Vulnerability class: Broken Access Control

Published 2026-10-12 · last modified 2026-10-12.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:N.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Zitadel

Weakness classification (CWE)

CWE-863 — Incorrect Authorization

References

github.com/zitadel/zitadel/security/advisories/GHSA-w4gv-rcwj-w6r5 (vendor-advisory)
www.vulncheck.com/advisories/zitadel-3.0.0-before-4.19.2-privilege-escalation-v… (third-party-advisory)

Frequently asked questions

What is CVE-2026-109374?: CVE-2026-109374 is a medium-severity vulnerability in Zitadel, classified under Incorrect Authorization. CVSS score: 5.5/10. Published 2026-10-12.
How severe is CVE-2026-109374?: Medium severity. CVSS v3 base score is 5.5 out of 10.