CVE-2026-56681
9Router: Authentication Bypass in Public LLM API via Spoofable X-9r-Real-Ip Header
- State
- Published
- Severity
- 7.3 High
- Published
- Sep 22, 2026
- Updated
- Sep 28, 2026
- Reserved
- Jun 22, 2026
Description
9Router is an AI router & token saver. Prior to 0.5.6, 9Router deployments that allow requests to reach Next.js without the sanitizing custom-server.js wrapper trust the client-supplied X-9r-Real-Ip header in src/dashboardGuard.js when isLocalRequest decides whether canAccessPublicLlmApi may skip API-key validation for /api/v1/* routes. A remote unauthenticated attacker can set X-9r-Real-Ip to 127.0.0.1 and be classified as a local client, including on the verified GET /api/v1/models route. This permits unauthorized use of the instance owner's configured LLM providers, consumption of paid credits, and enumeration of configured providers and models. This issue is fixed in version 0.5.6.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 7.3 High | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L | GitHub_M |
Weaknesses
- CWE-807 Reliance on Untrusted Inputs in a Security Decision
Affected Products
| Product | Versions |
|---|---|
9routerdecolua |
|
References
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