CVE-2026-42238 Unauthenticated Remote Code Execution via Backup Restore in nginx-ui
Unauthenticated attackers can achieve remote code execution by uploading a malicious backup archive during the initial startup window of nginx-ui.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-42238?
CVE-2026-42238 is a critical code injection vulnerability in 0xJacky nginx-ui, published on 4 May 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
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.
Weakness: CWE-94
Which versions are affected by CVE-2026-42238?
3 open source packages ship an affected version, including github.com/0xJacky/nginx-ui. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
github.com/0xJacky/nginx-ui Go | All versions | None |
github.com/0xJacky/nginx-ui Go | All versions | 2.3.8 |
github.com/0xJacky/nginx-ui Go | All versions | 2.3.8 |
Products include Nginxui Nginx Ui.
How do I fix CVE-2026-42238?
Upgrade github.com/0xJacky/nginx-ui to 2.3.8 or later.
Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.
Is CVE-2026-42238 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-42238 exists.
Other vulnerabilities in 0xJacky nginx-ui
- CVE-2026-33032 Nginx UI: Unauthenticated MCP Endpoint Allows Remote Nginx Takeover
- CVE-2026-27944 Nginx UI: Unauthenticated Backup Download with Encryption Key Disclosure
- CVE-2024-23827 Nginx-UI arbitrary file write through the Import Certificate feature
- CVE-2026-107806 Nginx UI: Authenticated Remote Code Execution via Backup Restore App Config Overwrite
- CVE-2026-33026 nginx-ui Backup Restore Allows Tampering with Encrypted Backups
Sources
Also known as GHSA-4pvg-prr3-9cxr, GO-2026-5129.