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.
History

Thu, 15 Oct 2026 03:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Mon, 12 Oct 2026 16:30:00 +0000

Type Values Removed Values Added
Description 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.
Title ZITADEL 3.0.0 before 4.18.0 Unauthenticated Username Change via Login V1
First Time appeared Zitadel
Zitadel zitadel
Weaknesses CWE-306
CPEs cpe:2.3:a:zitadel:zitadel:*:*:*:*:*:*:*:*
Vendors & Products Zitadel
Zitadel zitadel
References
Metrics cvssV3_1

{'score': 8.2, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L'}

cvssV4_0

{'score': 8.8, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published: 2026-10-12T16:05:44.304Z

Updated: 2026-10-15T02:55:04.399Z

Reserved: 2026-10-12T14:23:25.691Z

Link: CVE-2026-109371

cve-icon Vulnrichment

Updated: 2026-10-15T02:54:59.992Z

cve-icon NVD

Status : Deferred

Published: 2026-10-12T17:17:34.547

Modified: 2026-10-15T03:17:10.390

Link: CVE-2026-109371

cve-icon Redhat

No data.