Nginx UI: Cross-node authentication bypass via exposed node tokens
Summary
Nginx UI versions 2.0.0 up to but not including 2.5.0 return the cluster node token in the API responses of /api/nodes and /api/nodes/:id. Any authenticated user, including users without administrator rights, can read this token. The token is accepted as X-Node-Secret and grants the request the privileges of the internal initUser account, so an attacker can impersonate a trusted node against a reachable cluster member. This can expose sensitive management operations such as configuration synchronization and service restart.
Affected
- Nginx UI 2.0.0 up to but not including 2.5.0
- Vendor advisory: affected >= 2.0.0, < 2.5.0
Fixed in
- Fixed in Nginx UI 2.5.0 (fix commit 0ecbd106c37b5143be14880c9447a66135151512)
- Later releases, including 2.5.1 and 2.5.2, include the fix
Workaround
- Unknown. No vendor-published workaround found. Upgrading is the recommended fix.
Exploitation
- CISA SSVC: exploitation status poc, automatable: no, technical impact: total
- No public exploitation in the wild found at the time of research
- Attack requires a valid low-privileged login and network access to the Nginx UI instance
Our recommendation
- Upgrade Nginx UI to 2.5.0 or later, preferably the newest stable release
- Rotate the node secret (NGINX_UI_NODE_SECRET) on every instance and the JWT secret, then restart
- Rotate downstream credentials stored in Nginx UI and review administrator accounts and access logs for unauthorized activity
- In clusters, confirm that each node relationship shows 'Paired signature' before rotating shared secrets
- Restrict access to the admin interface to management networks and do not expose it to the internet
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- GitHub Security Advisory GHSA-32gc-wf3m-78w9 github.com
- Nginx UI release v2.5.0 github.com
- Fix commit 0ecbd106c37b5143be14880c9447a66135151512 github.com
- Nginx UI release v2.5.1 github.com
- OSV entry CVE-2026-107811 osv.dev
- Nginx UI node configuration guide nginxui.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 31 Oct 2026, 20:53.
Original description (NVD)
Nginx UI is a web user interface for the Nginx web server. From 2.0.0 until 2.5.0, ordinary authenticated users can access /api/nodes and /api/nodes/:id, whose responses serialize the node token field. The same token is accepted as X-Node-Secret by AuthRequired and maps the request to initUser, allowing the user to impersonate a trusted node against a reachable cluster member. This cross-node authentication bypass can expose sensitive management operations, including configuration synchronization and service restart. 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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