CVE-2026-61628 (GCVE-0-2026-61628)

Vulnerability from cvelistv5 – Published: 2026-09-21 14:44 – Updated: 2026-09-21 15:12
VLAI
Title
nginx ignition has Unauthenticated Admin Account Creation via Onboarding Race Condition
Summary
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.
Severity
8.1 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-21 15:12 UTC
CWE
  • CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7652 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
lucasdillmann nginx-ignition Affected: < 2.41.1
guessed Create a notification for this product.
Show details on NVD website
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