CVE-2026-105215

EUVD-2026-92108

04.10.2026, 15:16

ZITADEL before 3.4.14 and 4.x before 4.16.2 contains an authentication bypass in the hosted Login V1 UI because the 'external account not found' registration endpoint trusts client-supplied external identity fields without a completed IdP callback. Unauthenticated attackers can submit forged IDPConfigID and ExternalUserID values to pre-create an account bound to a victim's external IdP identity, which the victim's later genuine external login then signs into.

Provider	Type	Base Score	Atk. Vector	Atk. Complexity	Priv. Required	Vector
VulnCheck	CNA	9.1 CRITICAL	NETWORK	LOW	NONE	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Base Score

CVSS 3.x

EPSS Score

Percentile: Unknown

Early Detection

Affected products identified ahead of NVD analysis through intelligence sources.

Vendor	Product	Version	Source
zitadel	zitadel	𝑥 < 4.16.2	CNA
zitadel	zitadel	𝑥 < 3.4.14	CNA

Common Weakness Enumeration

CWE-290 - Authentication Bypass by Spoofing
This attack-focused weakness is caused by improperly implemented authentication schemes that are subject to spoofing attacks.

References

https://github.com/zitadel/zitadel/security/advisories/GHSA-738m-7888-jfv8

https://www.vulncheck.com/advisories/zitadel-before-4.16.2-account-pre-hijacking-via-forged-external-idp-callback