Vulnerability library
Security checkJune 19, 2026

Uni-CLI: Legacy HTTP MCP transport accepted browser-originated localhost requests

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High severitynpm@zenalexa/unicli

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Description

Uni-CLI versions before 0.225.2 exposed the legacy JSON-RPC-over-HTTP MCP transport on loopback without validating browser Origin headers before routing requests. A malicious web page could send a CORS simple POST request, such as text/plain, to the local /mcp endpoint and deliver a JSON-RPC body to the dispatcher.

Recommendation

Update the @zenalexa/unicli package to the latest compatible version. Followings are version details:

  • Affected version(s): < 0.225.2
  • Patched version(s): 0.225.2

References

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Related Issues

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