vulnerability / NVI-00016374 / Revision 1
9Router has an Authentication Bypass in Public LLM API via Spoofable X-9r-Real-Ip Header
GitHub lists this reviewed advisory for 9router. 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.
7.3 high
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.
9router
source listed<= 0.5.4
## Summary 9router determines whether an incoming request originates from localhost by trusting the X-9r-Real-Ip HTTP request header. This header is intended to be produced and sanitized exclusively by the bundled custom-server.js layer from the TCP socket address. In deployment modes where requests reach Next.js directly (the header is never stripped/regenerated), a remote, unauthenticated attacker can simply send X-9r-Real-Ip: 127.0.0.1 and be treated as a local client. This bypasses the API-key requirement on the public LLM API (/api/v1/*), granting unauthenticated access to the instance owner's configured provider resources. ## Affected Component - src/dashboardGuard.js - isLocalRequest() — trusts the client-supplied X-9r-Real-Ip header to decide loopback origin - canAccessPublicLlmApi() — grants access to /api/v1/* when isLocalRequest() returns true, skipping API-key validation - Verified affected route: GET /api/v1/models - Product version tested: 9router-app 0.5.4 (Next.js 16.2.9) ## Root Cause The authorization layer makes a security decision based on a client-controllable HTTP header. isLocalRequest() reads X-9r-Real-Ip and, if its value is a loopback address (
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-5mj8-gf6m-fhw8 ↗
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.