Input Validation
Agents or tools accept unsafe inputs that lead to downstream vulnerabilities or unexpected behavior.
Definition
Input Validation issues occur at the input layer of the Model Context Protocol (MCP). These attacks arise when agents or MCP-connected tools fail to validate user-supplied inputs, file contents, or external data. Unsafe inputs can trigger prompt injections, tool misfires, or even command execution through loosely typed or unsanitized parameters. In multi-tool workflows, unvalidated input at the start of the chain can ripple into critical failures downstream.
This attack lives in the input layer of the MCP model, where untrusted input first enters the system and influences agent decisions or tool behavior.
How MCP Security Helps
Akto identifies weak validation by injecting malformed, prompt-like, or malicious inputs into agent workflows. It tests how tools handle edge cases, verifies input schemas, and flags components that accept unsafe or loosely structured data without validation.
