CVE-2026-105215

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.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
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

Configurations

No configuration.

History

04 Oct 2026, 15:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-04 15:16

Updated : 2026-10-29 21:17

NVD link : CVE-2026-105215

Mitre link : CVE-2026-105215

CVE.ORG link : CVE-2026-105215

JSON object : View

Products Affected

No product.

CWE

CWE-290

Authentication Bypass by Spoofing

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