CVE-2026-105211

ZITADEL before 4.17.1 contains an authentication bypass vulnerability in Login V2 that allows unauthenticated attackers to take over accounts by obtaining OTP codes via the returnCode delivery type. Attackers knowing a login name of a victim with OTP-Email and OTP-SMS enrolled can read both codes from server-action responses to gain MFA-authenticated sessions, including administrator takeover.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

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-3gwm-5wx8-4gm6
https://www.vulncheck.com/advisories/zitadel-before-4.17.1-authentication-bypass-via-login-v2-otp-returncode

Configurations

No configuration.

History

04 Oct 2026, 15:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-04 15:16

Updated : 2026-10-05 15:17

NVD link : CVE-2026-105211

Mitre link : CVE-2026-105211

CVE.ORG link : CVE-2026-105211

JSON object : View

Products Affected

No product.

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

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