Decolua 9Router multiple authentication bypasses and sensitive data leaks

Executive brief

9Router, a tool used to manage and route AI model requests, contains multiple critical security flaws in its dashboard API. Unauthorized individuals can gain full control over AI provider connections, steal sensitive API keys for services like OpenAI or Anthropic, and read private conversation histories between users and AI assistants. This could lead to significant financial costs from stolen API keys, complete service disruption, and the exposure of confidential business data contained in AI prompts.

Technical details

Multiple Next.js API routes in 9Router lack authentication and authorization checks. The `/api/providers` endpoint allows unauthenticated attackers to perform CRUD operations on AI provider configurations, including injecting malicious proxies or deleting connections. The `/api/usage/stats` endpoint leaks full plaintext API keys (e.g., OpenAI `sk-` keys) and usage data. Furthermore, `/api/usage/request-details` allows unauthorized access to full conversation turns, including system prompts and assistant responses. These vulnerabilities stem from a lack of authentication middleware in the `src/app/api/*` directory. As of the advisory, no patch is available; users are advised to implement authentication middleware and mask sensitive keys in API responses.

Affected products

• decolua 9router <= 0.4.41

Timeline

• 2026-06-13: disclosed: Advisory published by reporter
• 2026-07-06: advisory: GitHub Advisory reviewed and updated

References

• https://api.github.com/users/newnol
• https://github.com/newnol
• https://api.github.com/users/newnol/gists%7B/gist_id%7D
• https://api.github.com/users/newnol/repos
• https://avatars.githubusercontent.com/u/88440500?v=4
• https://api.github.com/users/newnol/events%7B/privacy%7D