CVE-2026-42222

nginx-ui: Unauthenticated first-boot instance claim via POST /api/install allows remote bootstrap takeover

At a glance

Severity: HIGH 8.1
EPSS: EPSS 0.34 % · percentile 27 (2026-10-27)
State: PUBLISHED
Published: 2026-05-04
Updated: 2026-05-06
Assigner: GitHub_M
NVD status: Analyzed

Description

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.

Scores

Version	Score	Vector	Scored by
CVSS 3.1	HIGH 8.1	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H	GitHub_M
CVSS 3.1	HIGH 8.1	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H	NVD · security-advisories@github.com (Secondary)
CVSS 3.1	CRITICAL 9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H	NVD · nvd@nist.gov (Primary)

Weaknesses (CWE)

Advisories

GHSA-mxqh-q9h6-v8pq — Nginx-UI: Unauthenticated first-boot instance claim via POST /api/install allows remote bootstrap takeover
GO-2026-5521 — Nginx-UI: Unauthenticated first-boot instance claim via POST /api/install allows remote bootstrap takeover in github.com/0xJacky/nginx-ui

European references

ENISA EUVD · EUVD-2026-27137
GCVE · GCVE-0-2026-42222

Affected configurations (NVD CPE)

cpe:2.3:a:nginxui:nginx_ui:2.3.5:*:*:*:*:*:*:*

Affected products

Product	Versions
0xJacky · nginx-ui	affected = 2.3.5

References

https://github.com/0xJacky/nginx-ui/security/advisories/GHSA-mxqh-q9h6-v8pq

Sources

Source	Licence
CVE List (CVEProject cvelistV5)	CVE Program Terms of Use
EPSS (FIRST.org)	FIRST — attribution requested
ENISA EUVD	ENISA — reproduction authorised, source acknowledged
NVD (NIST) via fkie-cad/nvd-json-data-feeds	Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD