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Security audit

xlsx

Security checks for vulnerabilities and agentic risk

Overview

This spreadsheet skill is not clearly malicious, but it asks for broad command-execution and vague API/network authority without enough scoping for a spreadsheet tool.

Review before installing. Use only with spreadsheets you trust, avoid sensitive data unless you understand where it may be sent or processed, and require explicit approval before any command execution or API/network use. The artifact does not show destructive or exfiltration code, but its requested authority is broader than its spreadsheet purpose explains.

Vulnerability Patterns
  • Excessive AgencyUnrestricted Tool Access, Autonomous Decision Making, Scope Creep
  • Trigger AbuseOverly Broad Trigger, Shadow Command Trigger, Keyword Baiting Trigger
  • 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
Findings (6)

Description-Behavior Mismatch

Medium
Category
Not specified by scanner
Confidence
95% confidence
Finding

The skill is presented as a spreadsheet-processing tool, but its manifest and documentation expand into generic API, networking, and execution workflows unrelated to that purpose. This scope creep weakens least-privilege expectations and can mislead an agent into granting or using broader capabilities than a user would reasonably expect for spreadsheet handling.

Content

No source excerpt is available for this finding.

Context-Inappropriate Capability

High
Category
Not specified by scanner
Confidence
98% confidence
Finding

The manifest declares exec capability even though the stated purpose is ordinary spreadsheet processing. Allowing command execution in a file-handling skill materially increases the risk of arbitrary local command invocation, file tampering, or chaining user-controlled spreadsheet content into shell operations.

Content

No source excerpt is available for this finding.

Context-Inappropriate Capability

Medium
Category
Not specified by scanner
Confidence
92% confidence
Finding

The documentation introduces LLM API and external data-source/network dependencies without clearly tying them to spreadsheet-specific needs. This broadens the attack surface by enabling unnecessary outbound communication, possible data exfiltration, and trust in unspecified remote content.

Content

No source excerpt is available for this finding.

Intent-Code Divergence

Medium
Category
Not specified by scanner
Confidence
94% confidence
Finding

The file claims command execution is restricted to a whitelist, but there is no enforceable implementation or policy present in the skill definition. Security assertions without technical enforcement can create false trust and lead reviewers or agents to approve a risky capability that remains effectively unconstrained.

Content

No source excerpt is available for this finding.

Vague Triggers

High
Category
Not specified by scanner
Confidence
90% confidence
Finding

The trigger language is extremely broad, covering nearly any task where a spreadsheet file is involved. Over-broad activation can cause this skill to be invoked for routine requests unnecessarily, increasing exposure to its risky exec and network-related capabilities in contexts where simpler, safer handling would suffice.

Content

No source excerpt is available for this finding.

Vague Triggers

High
Category
Not specified by scanner
Confidence
91% confidence
Finding

The automatic trigger condition states the skill activates whenever the user needs related operations, but it does not define what qualifies or what guardrails apply. In a skill with execution and network-adjacent behavior, ambiguous auto-invocation increases the chance of unintended use on untrusted files or sensitive data.

Content

No source excerpt is available for this finding.

Static analysis

No suspicious patterns detected.