CVE-2026-105207
ZITADEL 3.0.0 through 3.4.15 and 4.0.0 before 4.17.3 creates links between user accounts and external identity providers without verifying a primary factor or the caller's permission, including on identify-only Login V2 sessions and via the User Service V2 AddIDPLink endpoint. An unauthenticated attacker knowing a victim's login name can bind their own external IdP identity to the victim's account and then sign in as the victim.
- Published Oct 4, 2026
- CVSS 9.3 critical
- 0.3% chance of exploitation in the next 30 days (EPSS)
- A fix is available