Vulnerability in 0xjacky Nginx-Ui
CVE-2026-84318
Nginx UI is a web user interface for the Nginx web server. From 2.0.0-rc.6 until 2.4.1, the MCP tool nginx_config_add writes nginx configuration files to disk and triggers an nginx reload without calling config.ValidateConfigFile. The identical flow in the REST API (POST /api/configs) does call that function and correctly rejects dangerous directives. An authenticated attacker can exploit this gap to write config files containing any blocked directive (perl, js_import, load_module, user root, etc.), bypassing nginx-ui's entire security layer. On a server with the nginx Perl, njs, or Lua module loaded, this is post-authentication Remote Code Execution. This issue is fixed in version 2.4.1.
Published .
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
- 0xjacky Nginx-Ui — versions >= 2.0.0-rc.6, < 2.4.1
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-84318?
- CVE-2026-84318 is a high-severity vulnerability in 0xjacky Nginx-Ui, classified under Protection Mechanism Failure. CVSS score: 8.8/10. Published 2026-10-12.
- How severe is CVE-2026-84318?
- High severity. CVSS v3 base score is 8.8 out of 10.