PenPot MCP REPL server binds to 0.0.0.0 with unauthenticated /execute endpoint — RCE — CVE-2026-45805

Summary

### Summary 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. ### Details `mcp/packages/server/src/ReplServer.ts:89`:…

Product

npm: @penpot/mcp

What to do

General, cautious steps (verify details in the official source):

• Prioritize patching or mitigation immediately (treat as actively risky).
• Identify affected product versions in your inventory and verify whether you are impacted.
• Apply vendor patches/updates or recommended mitigations as soon as available.
• Read the official advisory for exact affected versions and remediation steps.

Official advisory

• Read the official source
• CVE Record
• NVD

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