CyberRota Analysis
AI-GeneratedA type conversion vulnerability in BeamMCP.Server of ScriptKittyOS allows malicious MCP clients to manipulate boolean arguments, causing them to be interpreted as strings. This can lead to unintended behavior in hosts that differentiate between true and false values, particularly in security policies that may reject certain inputs. Organizations using beam_mcp versions from 0.1.0 to before 0.10.1 should prioritize remediation, especially if their applications rely on strict boolean evaluations.
Public Exploit Signal
A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.
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Original NVD Description
Incorrect Type Conversion or Cast vulnerability in BeamMCP.Server in ScriptKittyOS beam_mcp allows an MCP client's JSON true, false and null tool arguments to reach the host's dispatch function as the strings "true", "false" and "nil". After BeamMCP.Schema.validate/2 accepted a value as a boolean, normalize_arguments/2 passed every argument through to_json_value/1, whose atom clause converts true, false and nil to strings. A string is truthy in Elixir, so a host that tests a boolean argument, for example if args.dry_run, takes the opposite branch for false, and a guard such as confirm: false reads as set. The client controls the argument and could send true directly, so the practical impact is limited to hosts whose behaviour on false differs from their behaviour on true, and to any policy layer in front of the server that permits false but refuses true. The same normalisation applies to prompts/get arguments, which exist from 0.5.0. This issue affects beam_mcp: from 0.1.0 before 0.10.1.