---
title: "CVE-2026-42238: Nginx-UI is Vulnerable to Unauthenticated Remote Code Execution via Backup Restore"
url: https://erroneo.us/security/cve/CVE-2026-42238/
description: "CVE-2026-42238 (github.com/0xJacky/nginx-ui (Go)): Nginx UI is a web user interface for the Nginx web server. Prior to version 2.3.8, nginx-ui exposes a…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-05-04
date_modified: 2026-05-06
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-42238"
kev: false
cvss: 9
epss: 0.00832
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-42238: Nginx-UI is Vulnerable to Unauthenticated Remote Code Execution via Backup Restore

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Not in CISA KEV , but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
- EPSS 0.8% , percentile 57: FIRST’s model estimates a 0.8% chance of exploitation activity in the next 30 days, higher than 57% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Only applies if your dependency tree includes github.com/0xJacky/nginx-ui (Go) < 2.3.8, fixed in 2.3.8 . Check your lockfile, including transitive dependencies.

## What it is

Nginx UI is a web user interface for the Nginx web server. Prior to version 2.3.8, nginx-ui exposes a backup restore endpoint (POST /api/restore) that is completely unauthenticated during the first 10 minutes after process startup on any fresh installation. An unauthenticated remote attacker can upload a crafted backup archive that overwrites the application's configuration file (app.ini) and SQLite database. Because the attacker controls the restored app.ini, they can inject an arbitrary OS command into the TestConfigCmd setting. After the application automatically restarts to apply the restored config, a single follow-up request triggers that command as the user running nginx-ui — typically root in Docker deployments. This issue has been patched in version 2.3.8.

## Affected packages

- Go `github.com/0xJacky/nginx-ui` < 2.3.8 → fixed: 2.3.8

## Affected products (CVE record)

- 0xJacky nginx-ui: < 2.3.8

## Severity

- GitHub_M CVSS 4.0: 9 `CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H`
- GitHub CVSS 4.0: 9.0 `CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation poc , automatable no , technical impact total .
- FIRST EPSS (model of 2026-10-21): 0.83% probability of exploitation activity in the next 30 days; percentile 57.

## Sources

- [GitHub Advisory GHSA-4pvg-prr3-9cxr](https://github.com/advisories/GHSA-4pvg-prr3-9cxr)
- [CVE.org record CVE-2026-42238](https://www.cve.org/CVERecord?id=CVE-2026-42238)
- [NVD entry CVE-2026-42238](https://nvd.nist.gov/vuln/detail/CVE-2026-42238)
- [github.com](https://github.com/0xJacky/nginx-ui/security/advisories/GHSA-4pvg-prr3-9cxr)
- [github.com](https://github.com/0xJacky/nginx-ui/releases/tag/v2.3.8)

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Source page: https://erroneo.us/security/cve/CVE-2026-42238/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt