x64dbg-mcp-server: x64dbg-MCP Server vulnerable to pre-authentication denial of service through Content-Length integer overflow
What fixes it
- 1.2x64dbg-mcp-server, otherGitHub
A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.
Description
x64dbg-MCP Server is a native Model Context Protocol (MCP) plugin for x64dbg that exposes the debugger's full functionality over HTTP. Prior to 1.2, src/core/mcp_server.zig parses an unbounded Content-Length value in parseContentLength() and uses it in unchecked usize addition in wsRecv() before token authentication. The server listens on 0.0.0.0 by default in affected versions. An unauthenticated network client can supply a near-maximum Content-Length value to trigger a runtime integer-overflow panic in Debug and ReleaseSafe builds, terminating the entire x64dbg process and its live debugging session. The overflowed value is used only in a comparison, so the impact is limited to denial of service rather than memory corruption or code execution. This issue is fixed in version 1.2.
Text from CVE List
Affected versions 2
- x64dbg-mcp-serveraffected: < 1.2CVE List
- x64dbg-mcp-server, other<= 1.1GitHub
References 4
- github.com/duty1g/x64dbg-mcp-server/commit/0dd4204d37c81d8b605133dc48c14886eeac1562Fixvia CVE List
- github.com/duty1g/x64dbg-mcp-server/releases/tag/v1.2Fixvia CVE List
- github.com/duty1g/x64dbg-mcp-server/security/advisories/GHSA-jgj3-97w2-9v9rAdvisoryvia CVE List
- github.com/duty1g/x64dbg-mcp-server/security/advisories/GHSA-4478-h5jv-647mAdvisoryvia CVE List