CriticalCritical vulnerability
CVE-2026-105211 (CVSS 9.2)
NVD · officialPublished Oct 4, 2026Risk 50/100
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.
Technical details
CVSS
9.2
AV:NetworkAC:HighPR:NoneUI:None
Evidence and sources
This record is attributed to NVD. Exploitation status and remediation guidance are kept separate from the vulnerability's technical severity.
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