CVE-2026-105210: Zitadel

High severity, CVSS 8.2. EPSS: 0.2% chance of exploitation in the next 30 days.

ZITADEL 3.x before 3.4.15 and 4.x before 4.17.1 contains a missing authentication flaw in the hosted Login V1 UI, whose second-factor enrollment and initialization handlers act on an identify-only session before any primary factor is verified. Attackers knowing only a victim's login name can enroll attacker-controlled TOTP, OTP-SMS, OTP-Email, or U2F factors, overwrite the verified phone number, and enumerate users through discrepant errors.

Affected products

• Zitadel Zitadel: before 4.17.1 (fixed in 4.17.1); before 3.4.15 (fixed in 3.4.15)

Published 2026-10-04. Last modified 2026-10-05.