CVE-2026-42222 json
nginx-ui: Unauthenticated first-boot instance claim via POST /api/install allows remote bootstrap takeover
published 6mo ago modified 14d ago also EUVD-2026-27137 , GHSA-mxqh-q9h6-v8pq , GO-2026-5521
- cvss
- 8.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 27%
- public exploits
- 0
- none known
Summary
Nginx UI is a web user interface for the Nginx web server. In version 2.3.5, an unauthenticated bootstrap takeover exists in nginx-ui during the initial installation window exposed by POST /api/install. At time of publication no public patches are available.
Patch / fix
- govulncheck-vulndb openSUSE Leap 16.0 0.0.20260723T184607-160000.1.1
opensuse advisories openSUSE-SU-2026:21483-1
Is CVE-2026-42222 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- total
- Assessed
- 6mo ago
Exploit prediction
0.34% chance of exploitation in the next 30 days, higher than 27% of all scored CVEs (FIRST EPSS, 2026-11-09).
Exploits and checks
- github.com https://github.com/0xJacky/nginx-ui/security/advisories/GHSA-mxqh-q9h6-v8pq referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |
| GitHub | 3.1 | 8.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| go | github.com/0xJacky/nginx-ui | 1 listed version all versions |
no fix listed |
Affected products
- 0xJacky nginx-ui
Classification
References
-
github.com
/0xJacky/nginx-ui/security/advisories/GHSA-mxqh-q9h6-v8pq
exploit, web, vendor-advisory, advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-42222
advisory
-
github.com
/0xJacky/nginx-ui
package
Sources
- CVE List CVE-2026-42222
- GitHub Advisory GHSA-mxqh-q9h6-v8pq
- NVD CVE-2026-42222
- OSV GO-2026-5521
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.