9router, an AI router and token saver by decolua, protects several API endpoints (/v1, /v1beta, /api/v1, /api/v1beta) via src/dashboardGuard.js but omits protection for the /codex endpoint. Before version 0.5.2, requests to /codex/* bypass the API-key gate because next.config.mjs rewrites /codex/* to /api/v1/responses without enforcing authorization. This missing authorization (CWE-862) allows remote unauthenticated attackers to trigger upstream provider calls using operator credentials, potentially leading to information disclosure and service disruption. The vulnerability is addressed in version 0.5.2.

An unauthenticated remote attacker can bypass API-key authorization by sending requests to the /codex endpoint, causing the server to make upstream calls with operator-stored LLM provider credentials. This can lead to unauthorized use of provider resources, potential data leakage (confidentiality impact), integrity issues, and high availability impact due to misuse of service calls. The CVSS 3.1 base score is 8.6 (High), reflecting network attack vector, low attack complexity, no privileges required, no user interaction, and impacts to confidentiality, integrity, and availability.

This vulnerability is fixed in decolua 9router version 0.5.2. Users should upgrade to version 0.5.2 or later to remediate the issue. No other official remediation or temporary fixes are documented. Patch status is confirmed fixed in 0.5.2.