Vulnerability library
Security checkMay 19, 2026

PenPot MCP REPL server binds to 0.0.0.0 with unauthenticated /execute endpoint — RCE

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High severitynpm@penpot/mcp

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Description

The MCP module’s ReplServer binds to all interfaces (0.0.0.0:4403) and exposes a /execute endpoint that runs arbitrary code with zero authentication. Anyone on the network can POST JavaScript and it runs on the server. The main PenpotMcpServer was partially fixed for a similar binding issue (#8683), but ReplServer.ts was missed.

Recommendation

Update the @penpot/mcp package to the latest compatible version. Followings are version details:

  • Affected version(s): < 2.15.0
  • Patched version(s): 2.15.0

References

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Related Issues

See something that needs correcting? Let us knowUpdated May 19, 2026