Biome Config Validator

• Outcome: Pass
• Latest audit: Sep 16, 2026 · 5:58 AM UTC
• Version: 1.0.1

Overview

This skill is a local Biome config checker with a minor capability mismatch, but no evidence of hidden access, persistence, network use, or data exfiltration.

Installers should understand that the validator appears safe and local-only, but the advertised conflict checking is incomplete and should not be relied on as a complete Biome rule-conflict audit.

A.I.G

Vulnerability Patterns

• Skill Instruction Hijacking: Alters the agent's session goals or safety constraints when the skill loads
• Agent Memory Poisoning: Writes attacker-controlled rules into memory that affect later sessions
• Remote Payload Retrieval and Execution: Fetches external code whose behavior can change after review
• Embedded Malicious Code: Ships malicious scripts inside the skill and executes them locally
• Unauthorized Access and Privilege Escalation: Obtains permissions beyond the task's legitimate needs

SkillSpector

Vulnerability Patterns

• MCP Least Privilege: Underdeclared Capability, Wildcard Permission, Missing Permission Declaration
• MCP Tool Poisoning: Hidden Instructions, Unicode Deception, Parameter Description Injection
• Prompt Injection: Instruction Override, Hidden Instructions, Exfiltration Commands
• Data Exfiltration: External Transmission, Env Variable Harvesting, File System Enumeration
• Privilege Escalation: Excessive Permissions, Sudo/Root Execution, Credential Access

Findings (8)

Tp4

High

• Category: MCP Tool Poisoning
• Confidence: 95% confidence

Finding

The code generally aligns with the stated purpose of validating and linting Biome configuration files: it parses biome.json, checks top-level structure, validates formatter/linter options, flags deprecated rules, and emits best-practice recommendations. It also has commands named lint, deprecated, validate, and conflicts. However, there is a material description-behavior mismatch because conflict detection is explicitly claimed in the description, yet the script never uses CONFLICTING_PAIRS and the 'conflicts' command simply calls lint_rules(), which does not evaluate rule conflicts at all. Compatibility checking is also only loosely represented through a few deprecated/unknown validations rather than a dedicated compatibility pass. No suspicious undeclared behaviors like network access, exfiltration, or unrelated actions are present.

Content

No source excerpt is available for this finding.

Ae1

High

• Category: analysis-evasion
• Confidence: 100% confidence

Finding

Referenced artifact was not completely inspected

Content

Scanner excerpt · SKILL.md (reported line 14)May include surrounding context.

md

python3 scripts/biome_config_validator.py lint biome.json

Ae1

High

• Category: analysis-evasion
• Confidence: 100% confidence

Finding

Referenced artifact was not completely inspected

Content

Scanner excerpt · SKILL.md (reported line 17)May include surrounding context.

md

python3 scripts/biome_config_validator.py lint biome.json

Ae1

High

• Category: analysis-evasion
• Confidence: 100% confidence

Finding

Referenced artifact was not completely inspected

Content

Scanner excerpt · SKILL.md (reported line 20)May include surrounding context.

md

python3 scripts/biome_config_validator.py lint biome.json

Ae1

High

• Category: analysis-evasion
• Confidence: 100% confidence

Finding

Referenced artifact was not completely inspected

Content

Scanner excerpt · SKILL.md (reported line 23)May include surrounding context.

md

python3 scripts/biome_config_validator.py lint biome.json

Ae1

High

• Category: analysis-evasion
• Confidence: 100% confidence

Finding

Referenced artifact was not completely inspected

Content

Scanner excerpt · SKILL.md (reported line 26)May include surrounding context.

md

python3 scripts/biome_config_validator.py lint biome.json

Ae1

High

• Category: analysis-evasion
• Confidence: 100% confidence

Finding

Referenced artifact was not completely inspected

Content

Scanner excerpt · SKILL.md (reported line 29)May include surrounding context.

md

python3 scripts/biome_config_validator.py lint biome.json

Undeclared Tool Scope

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.

Static analysis

No suspicious patterns detected.