nginx ignition is a user interface for the nginx web server. Prior to version 2.41.1, `POST /api/users/onboarding/finish` is registered as anonymous (unauthenticated) and creates a user with full ReadWrite admin permissions. Because the handler uses a check-then-act (TOCTOU) pattern between the "onboarding already completed?" check and the user-creation write, with no atomic guard, a remote unauthenticated attacker who can reach an instance in its pre-onboarding state can create an administrator account for themselves — and concurrent requests can create multiple admin accounts in a single race. Version 2.41.1 patches the issue.

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History

Mon, 21 Sep 2026 19:45:00 +0000

Type Values Removed Values Added
First Time appeared Lucasdillmann
Lucasdillmann nginx-ignition
Vendors & Products Lucasdillmann
Lucasdillmann nginx-ignition

Mon, 21 Sep 2026 16:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Mon, 21 Sep 2026 15:00:00 +0000

Type Values Removed Values Added
Description nginx ignition is a user interface for the nginx web server. Prior to version 2.41.1, `POST /api/users/onboarding/finish` is registered as anonymous (unauthenticated) and creates a user with full ReadWrite admin permissions. Because the handler uses a check-then-act (TOCTOU) pattern between the "onboarding already completed?" check and the user-creation write, with no atomic guard, a remote unauthenticated attacker who can reach an instance in its pre-onboarding state can create an administrator account for themselves — and concurrent requests can create multiple admin accounts in a single race. Version 2.41.1 patches the issue.
Title nginx ignition has Unauthenticated Admin Account Creation via Onboarding Race Condition
Weaknesses CWE-362
References
Metrics cvssV3_1

{'score': 8.1, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H'}


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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-09-21T15:12:59.314Z

Reserved: 2026-07-10T17:38:57.110Z

Link: CVE-2026-61628

cve-icon Vulnrichment

Updated: 2026-09-21T15:12:47.399Z

cve-icon NVD

Status : Received

Published: 2026-09-21T15:17:30.290

Modified: 2026-09-21T15:17:30.290

Link: CVE-2026-61628

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-21T19:23:31Z

Weaknesses