CVSS 3.1
8.1 highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:HCVE-2026-61628
High (8.1). EPSS 0.4% chance of exploitation in the next 30 days. Fixed in github.com/lucasdillmann/nginx-ignition 0.0.0-20260621194639-0586b4e55ab.
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
- EPSS
- 0.4% chance of exploitation in the next 30 days; higher than 37% of CVEs (scores of 2026-10-31)
- CWE
- CWE-362
- Published
- Modified
- Record from
- the NVD, synced
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-pxcx-fv34-x9p5 | Go | github.com/lucasdillmann/nginx-ignition | <0.0.0-20260621194639-0586b4e55ab | 0.0.0-20260621194639-0586b4e55ab |
| GO-2026-6540 | Go | github.com/lucasdillmann/nginx-ignition | all versions | no fix published |