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Security audit

proposal-builder

Security checks for vulnerabilities and agentic risk

Overview

This skill creates local proposal drafts for human review, but its renderer has correctness problems that require careful checking.

Treat outputs as drafts. The script expects CSV despite the Markdown quickstart; verify prices, terms, signatures, and unresolved placeholders manually. Use a fresh output folder because matching filenames can be overwritten. The optional unsigned Windows app needs a separate trust decision; matching its supplied hash does not establish safety.

Vulnerability Patterns
  • Skill Instruction HijackingAlters the agent's session goals or safety constraints when the skill loads
  • Agent Memory PoisoningWrites attacker-controlled rules into memory that affect later sessions
  • Remote Payload Retrieval and ExecutionFetches external code whose behavior can change after review
  • Embedded Malicious CodeShips malicious scripts inside the skill and executes them locally
  • Unauthorized Access and Privilege EscalationObtains permissions beyond the task's legitimate needs
Vulnerability Patterns
  • MCP Least PrivilegeUnderdeclared Capability, Wildcard Permission, Missing Permission Declaration
  • MCP Tool PoisoningHidden Instructions, Unicode Deception, Parameter Description Injection
  • Prompt InjectionInstruction Override, Hidden Instructions, Exfiltration Commands
  • Data ExfiltrationExternal Transmission, Env Variable Harvesting, File System Enumeration
  • Privilege EscalationExcessive Permissions, Sudo/Root Execution, Credential Access
Findings (3)

Description-Behavior Mismatch

High
Category
MCP Tool Poisoning
Confidence
97% confidence
Finding

The code supports the proposal-rendering portion of the description, but not its explicit validation claim. It does not verify required fields, inspect signature blocks, check pricing, or report missing information or unresolved placeholders. This is a material functional mismatch, rather than an unrelated or malicious capability.

Content

No source excerpt is available for this finding.

Skill declares no tool scope ('permissions' or 'allowed-tools') but code capabilities were detected: file_write.

Medium
Category
MCP Least Privilege
Confidence
70% confidence
Finding

Without declared permissions the skill's intent is opaque and cannot be validated.

Content

No source excerpt is available for this finding.

Proposal rendering omits the gap checks promised by the manifest.

Medium
Category
Excessive Agency
Confidence
98% confidence
Finding

The renderer silently substitutes empty strings for missing CSV fields and writes proposals without checking required scope, pricing, dates, or terms, despite the skill description promising gap checks. Malformed or deliberately incomplete input can therefore produce apparently finished proposals with material omissions, creating financial or contractual risk if users rely on the advertised validation. This is a business-document integrity weakness rather than evidence of malicious behavior or code execution.

Content

No source excerpt is available for this finding.

Static analysis

No suspicious patterns detected.