CVE-2026-109371
ZITADEL 3.0.0 before 4.18.0 Unauthenticated Username Change via Login V1
Published Oct 12, 2026 · updated Oct 15, 2026 · zitadel zitadel
ZITADEL 3.0.0 before 4.18.0 contains a missing authentication vulnerability in the hosted Login V1 UI, where the change-username handler acts on the account bound to a login flow before any factor is verified. Unauthenticated attackers can submit a victim's login name and then post a new username to rename any active human user, including administrators, locking them out.
Timeline
Detection, updates, and resolution for this record.
Oct 12, 2026 · NIST NVD
Detected
ZITADEL 3.0.0 before 4.18.0 contains a missing authentication vulnerability in the hosted Login V1 UI, where the change-username handler acts on the account bound to a login flow before any factor is verified. Unauthenticated attackers can submit a victim's login name and then post a new username to rename any active human user, including administrators, locking them out.
Oct 15, 2026 · NIST NVD
Updated
ZITADEL 3.0.0 before 4.18.0 contains a missing authentication vulnerability in the hosted Login V1 UI, where the change-username handler acts on the account bound to a login flow before any factor is verified. Unauthenticated attackers can submit a victim's login name and then post a new username to rename any active human user, including administrators, locking them out.
Affected
- vendor zitadel zitadelversion unspecified
Sources
- CIRCL Vulnerability LookupCVE-2026-109371
ZITADEL 3.0.0 before 4.18.0 contains a missing authentication vulnerability in the hosted Login V1 UI, where the change-username handler acts on the account bound to a login flow before any factor is verified. Unauthenticated attackers can submit a victim's login name and then po
vulnerability.circl.lu - CVE.orgCVE-2026-109371
Official CVE identifier
cve.org - NIST NVDCVE-2026-109371
ZITADEL 3.0.0 before 4.18.0 contains a missing authentication vulnerability in the hosted Login V1 UI, where the change-username handler acts on the account bound to a login flow before any factor is verified. Unauthenticated attackers can submit a victim's login name and then po
nvd.nist.gov