CVE-2026-54547

Name of the Vulnerable Software and Affected Versions meta-ads-mcp versions prior to 1.0.115

Description An authentication bypass exists in the AuthInjectionMiddleware within the meta-ads-mcp package. The middleware only rejects requests when both auth token and pipeboard token are absent. However, the extract token from headers() function does not recognize the X-Pipeboard-Token header, while extract pipeboard token from headers() does. By providing the X-Pipeboard-Token header with any arbitrary value, an attacker can satisfy the guard condition and bypass authentication.

Once bypassed, no authentication context is set, causing the system to fall back to the server operator's META ACCESS TOKEN environment variable. This allows an unauthenticated network caller to execute MCP tool calls using the operator's privileged Meta credentials, enabling them to read and write Meta Ads data, including ad accounts, campaigns, and budgets. The issue is specifically present when the server is deployed in streamable-http mode.

Recommendations Update to version 1.0.115 or later. As a temporary mitigation, restrict network access to the /mcp endpoint to trusted sources only.