Vulnerability Description
MoLing is a computer-use and browser-use based MCP server. Prior to 0.5.0, when MoLing runs in SSE mode using `-l`, its `/sse` and `/message` HTTP endpoints do not authenticate requests and the `mcp-go` dependency sets `Access-Control-Allow-Origin: *`. A malicious web page can open a cross-origin `EventSource` to `/sse`, including a loopback listener, and read the `endpoint` event to obtain `sessionId`. After a victim running SSE mode visits that page, the attacker can use the disclosed `sessionId` against `/message` to send unauthorized MCP tool calls. Depending on the configured tools, those calls can read or write local files, execute commands or perform other actions. Binding only to loopback does not prevent this browser-mediated attack. This issue is fixed in version 0.5.0.
CVSS Score
CRITICAL
Related Weaknesses (CWE)
References
- https://github.com/gojue/moling/commit/ae07f704cbc88d4419fc0fbaec278090fcd0502d
- https://github.com/gojue/moling/pull/48
- https://github.com/gojue/moling/releases/tag/v0.5.0
- https://github.com/gojue/moling/security/advisories/GHSA-qpgh-hp5g-4vwp
FAQ
What is CVE-2026-62863?
CVE-2026-62863 is a vulnerability with a CVSS score of 9.6 (CRITICAL). MoLing is a computer-use and browser-use based MCP server. Prior to 0.5.0, when MoLing runs in SSE mode using `-l`, its `/sse` and `/message` HTTP endpoints do not authenticate requests and the `mcp-g...
How severe is CVE-2026-62863?
CVE-2026-62863 has been rated CRITICAL with a CVSS base score of 9.6/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2026-62863?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.