Auth bypass in Zitadel
CVE-2026-105210
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.
Vulnerability class: Broken Authentication
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/zitadel/zitadel/security/advisories/GHSA-72q5-mv5c-vxv4 (vendor-advisory)
- www.vulncheck.com/advisories/zitadel-before-4.17.1-unauthenticated-mfa-enrollme… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-105210?
- CVE-2026-105210 is a high-severity vulnerability in Zitadel, classified under Improper Authentication. CVSS score: 8.2/10. Published 2026-10-04.
- How severe is CVE-2026-105210?
- High severity. CVSS v3 base score is 8.2 out of 10.