Nginx UI: Arbitrary file write via symlink during backup restore
Summary
Nginx UI, a web interface for managing Nginx, contains a symlink-following flaw in its backup restore function. An authenticated user with backup create and restore rights can craft a backup archive that writes attacker-controlled files into the live Nginx configuration path, even when the restore options for Nginx and Nginx UI are disabled. Successful exploitation can lead to persistent configuration tampering or denial of service once the modified files are used.
Affected
- Nginx UI (0xJacky) versions 2.0.0 up to but not including 2.5.0
- Sources differ on the exact upper bound (some state 2.4.9 or 2.4.x); treat all versions before 2.5.0 as affected
Fixed in
- Version 2.5.0 (fix commit a467ed652591aa1 referenced in the advisory)
- Latest stable 2.5.x release recommended; v2.5.1 states it includes all v2.5.0 changes
Workaround
Unknown.
Exploitation
- Requires a valid account with backup create and restore rights
- CISA SSVC: exploitation status poc, not automatable
- No public exploit or evidence of in-the-wild exploitation found at time of research
Our recommendation
- Upgrade Nginx UI to the latest stable 2.5.x release
- Limit backup create and restore rights to the minimum number of administrators
- Do not restore backups from untrusted sources
- Keep the admin interface off the public internet and restrict access to it
- Review the v2.5.0 release notes on credential rotation if the instance ran 2.3.6 or earlier
- Check related issue CVE-2026-107806 together with this CVE
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- GitHub Security Advisory GHSA-p8v3-89rh-jxc7 github.com
- Nginx UI release v2.5.0 github.com
- Fix commit a467ed652591aa1 github.com
- OSV record CVE-2026-107810 osv.dev
- Go advisory range (GitLab Advisory Database) advisories.gitlab.com
- VulDB entry 415950 vuldb.com
- Nginx UI release v2.5.1 github.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 1 Nov 2026, 20:25.
Original description (NVD)
Nginx UI is a web user interface for the Nginx web server. From 2.0.0 until 2.5.0, internal/backup/restore.go extracts inner archives before applying the restore_nginx and restore_nginx_ui flags and permits symlinks targeting the live Nginx configuration path. An authenticated user who can create and restore backups can craft a valid backup that places a symlink in the staging tree and then writes a regular file through that link, even when both restore flags are false. This can persistently inject configuration or cause denial of service when the modified files are later consumed. This issue is fixed in version 2.5.0.
NVD references (4)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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