CVE-2025-66454

Summary

Arcade MCP allows you to to create, deploy, and share MCP Servers. Prior to 1.5.4, the arcade-mcp HTTP server uses a hardcoded default worker secret ("dev") that is never validated or overridden during normal server startup. As a result, any unauthenticated attacker who knows this default key can forge valid JWTs and fully bypass the FastAPI authentication layer. This grants remote access to all worker endpoints—including tool enumeration and tool invocation—without credentials. This vulnerability is fixed in 1.5.4.

Affected Software

VendorProductVersion RangeStatus
ArcadeAIarcade-mcp< 1.5.4affected

Weaknesses

  • CWE-321: CWE-321: Use of Hard-coded Cryptographic Key
  • CWE-798: CWE-798: Use of Hard-coded Credentials

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: poc
    • Automatable: no
    • Technical Impact: partial

References