CVE-2026-105215: ZITADEL authentication bypass in Login V1 UI

CVE-2026-105215 · Severity: critical · CVSS 9.1 · Published 2026-10-04

ZITADEL is an open-source identity and access management platform that handles user authentication. An attacker can forge external identity provider credentials to pre-create accounts bound to a victim's external identity, then hijack the victim's login when they authenticate normally. This allows account takeover without needing access to the victim's external identity provider account.

Technologies: ZITADEL. Vendors: ZITADEL.

Quick answers

Is CVE-2026-105215 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-105215 being exploited in the wild.
How severe is CVE-2026-105215?
Critical severity, with a CVSS score of 9.1, published 4 October 2026.
Which products and versions are affected?
ZITADEL 3.0.0 through 3.4.13, 4.0.0 through 4.16.1.
Is there a fix for CVE-2026-105215?
Yes: fixed in ZITADEL 3.4.14, 4.16.2. Until then: If immediate upgrade is not possible, disable "Account creation allowed (manually)" on each configured external IdP. This blocks the vulnerable registration path but disables legitimate self-service account creation via that IdP; automatic account creation after verified IdP callback is not affected. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-105215 attacked?
It is attacked over the network, in a hosted service.
Am I affected by CVE-2026-105215?
Check whether you run ZITADEL at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • Fixed in: ZITADEL 3.4.14, 4.16.2

If immediate upgrade is not possible, disable "Account creation allowed (manually)" on each configured external IdP. This blocks the vulnerable registration path but disables legitimate self-service account creation via that IdP; automatic account creation after verified IdP callback is not affected.

Technical details

ZITADEL's Login V1 UI "external account not found" registration endpoint trusts client-supplied IDPConfigID and ExternalUserID values without requiring a completed IdP callback verification. An unauthenticated attacker can submit forged external identity fields to pre-create an account bound to any external IdP identity, which is then hijacked when a victim with that identity performs a genuine external login. Login V2 is unaffected as it uses cryptographically bound IdP intents.

Affected products

  • ZITADEL ZITADEL 3.0.0 through 3.4.13, 4.0.0 through 4.16.1

Timeline

  • 2026-07-29: disclosed: GitHub security advisory published
  • 2026-10-04: advisory: Public disclosure via NVD

References

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