CVE-2026-105207

ZITADEL 3.0.0 through 3.4.15 and 4.0.0 before 4.17.3 creates links between user accounts and external identity providers without verifying a primary factor or the caller's permission, including on identify-only Login V2 sessions and via the User Service V2 AddIDPLink endpoint. An unauthenticated attacker knowing a victim's login name can bind their own external IdP identity to the victim's account and then sign in as the victim.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/zitadel/zitadel/security/advisories/GHSA-g8gj-gq47-xgf4
https://www.vulncheck.com/advisories/zitadel-before-4.17.3-account-takeover-via-external-idp-linking

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-2026-105207

Mitre link : CVE-2026-105207

CVE.ORG link : CVE-2026-105207

JSON object : View

Products Affected

No product.

CWE

CWE-306

Missing Authentication for Critical Function

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