Description
ZITADEL 4.0.0 before 4.19.5 contains an authentication bypass vulnerability in the Login V2 UI that allows unauthenticated attackers to set the first credential of users lacking any authentication method. Attackers can compute a valid verificationCheck cookie from the user ID and browser fingerprint to set a password, register a passkey, or link an identity provider, taking over the account.
References2
Metrics
- CVSS 3.1
-
7.4
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N - CVSS 4.0
-
9.1
CRITICAL
Score source: CNA
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 21 · as of 3 November 2026
- CWE
- CWE-565
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.