Authentication Bypass in ZITADEL Login UI Before Primary Verification

ZITADEL 3.x before 3.4.14 and 4.x before 4.16.2 contains an authentication bypass in the hosted Login V1 and Login V2 UIs that accepts passkey or other authenticator enrollment on identify-only login sessions, before any primary factor is verified. Unauthenticated attackers knowing only a victim's login name can register an attacker-controlled authenticator and log in as that user, bypassing existing passwords and MFA.

Casky was already ahead

This CVE exploits attack patterns that Casky's 283matched skills already investigate — long before this vulnerability was disclosed. Claude's reasoning model maps these techniques to MITRE ATT&CK, so practitioners who ran these skills have already seen the threat behaviour in their findings.

Analysis

ZITADEL versions 3.x before 3.4.14 and 4.x before 4.16.2 contain a critical authentication bypass vulnerability in their hosted Login V1 and Login V2 user interfaces. The flaw allows unauthenticated attackers to enroll passkeys or other authenticators during identify-only login sessions—before any primary authentication factor has been verified. An attacker who knows only a victim's login name can register their own authenticator and gain full account access, completely circumventing existing passwords and multi-factor authentication. This affects any organization deploying vulnerable ZITADEL versions as their identity and access management system, putting all downstream applications and services at risk of account takeover.

Casky's 283 mapped skills detect the attack patterns behind this CVE by analyzing behaviors aligned with MITRE ATT&CK techniques TA0004 (Privilege Escalation) and TA0006 (Credential Access). Extended Claude reasoning identifies anomalies such as authenticator enrollment requests originating from unauthenticated sessions, missing validation gates in the login flow, and rapid enrollment-to-login sequences from new authenticator identities. Practitioners using Casky would observe findings flagging premature authenticator registration attempts, lack of primary factor verification before secondary factor enrollment, and authentication state machine bypasses—providing visibility into exploitation patterns before account compromise occurs and enabling rapid patching or compensating controls.

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Casky Risk Score

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EPSS Probability

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Shodan Exposure

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GreyNoise Signal

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283 Casky skills cover this attack pattern

These skills use Claude AI's reasoning model to surface findings in the same attack categories as CVE-2026-105212.

abusing-dpapi-for-credential-access

red teaming · high

Run

abusing-shadow-credentials-for-privesc

red teaming · high

Run

Access with Stolen Session Cookie

identity access management · low

Run

MITRE ATT&CK Techniques

TA0004 TA0006

Investigate the attack patterns behind CVE-2026-105212

Casky has 283 skills that investigate the attack patterns behind CVE-2026-105212. Run one and get CVSS-scored findings in 3 minutes.

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