ContextForge mcp-contextforge-gateway Pre-Auth JWT Token Forgery via Hardcoded Secret (CWE-321)

Vulnerability Overview Vulnerability Name: Hardcoded Default JWT_SECRET_KEY Allows Pre-authentication Platform Admin Token Forgery (CWE-321) Vulnerability Description: ContextForge hardcodes an HMAC-SHA256 signing key as the default for production environments in its source code and file. Attackers can exploit this hardcoded key to forge platform administrator tokens, bypassing the authentication mechanism without needing to provide credentials or account information. Vulnerability Types: Hardcoded Key (CWE-321), Insecure Default Configuration (CWE-327), Improper Authentication (CWE-287) Scope of Impact Affected Versions: package, versions = 1.0.2 Severity: 9.8 / 10 (Critical) Attack Vector: Network Attack Complexity: Low Required Privileges: None User Interaction: None Impact: High (Confidentiality, Integrity, Availability) Remediation 1. Refuse to use known weak keys: Convert into an environment variable and use weak values in the development environment. 2. Automatically generate keys: Automatically generate and upon first startup if they match the hardcoded weak values. 3. Stop using weak values: Replace the weak values in and refuse to start if weak values are detected. 4. Decrypt Platform Admin Onboarding: Decrypt the platform admin onboarding from email matching, requiring or a dedicated one-step onboarding token. 5. Make the default: Once applied, the onboarding process will no longer lock the operator. POC Code Exploitation Steps 1. Confirm authentication is enforced: 2. Confirm the forged token is accepted as platform admin: 3. Confirm admin scope is granted: 4. Confirm the attack remains effective after the admin account is deleted: Impact Pre-authentication, network-accessible attackers can forge platform administrator tokens to access all resources. Read and write access to all managed tools, gateways, servers, prompts, resources, and cross-team tenants. Read access to stored OAuth client secrets and other user credentials. Create, modify, and delete users; delete or lock legitimate administrator accounts. Register arbitrary upstream MCP servers and tools, enabling lateral movement and supply chain attacks. Indefinite re-entry without account status changes: Deleting , rotating passwords, revoking sessions, or clearing will not revoke the attacker's ability to create new tokens. Conclusion This vulnerability allows attackers to forge platform administrator tokens via hardcoded JWT keys, thereby gaining full control over the system. It is recommended to upgrade to the fixed version as soon as possible or implement the remediation measures described above.

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ContextForge mcp-contextforge-gateway Pre-Auth JWT Token Forgery via Hardcoded Secret (CWE-321)

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