vulnerability / NVI-00011827 / Revision 1
Nginx UI: Bundled reverse proxy can bypass IP allowlists and enable shared login lockout
GitHub lists this reviewed advisory for github.com/0xJacky/Nginx-UI. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
5.3 medium
GitHub source severity; exploitability and local consequence require separate evidence.
As of · GitHub Advisory Database
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
github.com/0xJacky/Nginx-UI
source listed>= 1.9.10-0.20251005005631-6de168c9454, < 1.9.10-0.20260904075558-e30e331303fc
## Summary In Nginx UI versions 2.2.0 through 2.5.x, the official bundled reverse-proxy topology did not preserve the external client identity used by Gin. The backend treated the local proxy peer as the client because no trusted proxy was configured, while the proxy supplied the actual address in forwarding headers. ## Impact This has two distinct effects in bundled-proxy deployments: * **IP allowlist enforcement:** management API requests forwarded by the bundled proxy were identified as loopback and could pass the loopback exception even when the external source was not in the configured allowlist. Protected management operations still required valid credentials; this did not grant unauthenticated administrator access. * **Login availability:** failed login attempts from different external sources were attributed to one loopback address. An unauthenticated attacker could therefore trigger the shared temporary login-ban threshold and deny password or OTP login to other users behind the proxy until the ban expired. Existing authenticated sessions were not invalidated. ## Remediation Upgrade to Nginx UI 2.6.0 or later. The fix explicitly trusts only the intended bundled proxy
03 / Response
What to do next
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-9h23-53f4-q947 ↗
GitHub Advisory Database · vendor advisory
Observed . GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.
Public revision history
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- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.