Security audit

Violin

Security checks for vulnerabilities and agentic risk

Overview

This violin coaching skill is purpose-aligned and low risk, with a disclosed but somewhat eager local progress-log feature.

Install only if you are comfortable with the agent creating a ~/violin/ folder and saving violin practice details there. Ask the agent not to save logs, or to confirm before writing, if you want session-only advice.

A.I.G

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

SkillSpector

Vulnerability Patterns

Data ExfiltrationExternal Transmission, Env Variable Harvesting, File System Enumeration
Trigger AbuseOverly Broad Trigger, Shadow Command Trigger, Keyword Baiting Trigger
Prompt InjectionInstruction Override, Hidden Instructions, Exfiltration Commands
Privilege EscalationExcessive Permissions, Sudo/Root Execution, Credential Access
Supply ChainUnpinned Dependencies, External Script Fetching, Obfuscated Code

Findings (4)

Missing User Warnings

Medium

Confidence: 95% confidence
Finding: The skill instructs the agent to create a persistent directory in the user's home folder on first interaction without explicit user consent or a warning that filesystem changes will occur. Even though the action is low-risk in isolation, silent writes to the home directory violate least surprise and can normalize unauthorized persistence behavior.

Missing User Warnings

Medium

Confidence: 93% confidence
Finding: The skill proposes logging progress to a file in the user's home directory but does not disclose retention, contents, or ask for permission before storing user practice data. Persistent storage of user-generated information without clear notice creates privacy and consent risks, even if the data seems non-sensitive.

Missing User Warnings

Medium

Confidence: 91% confidence
Finding: The progress-tracking section explicitly directs persistent logging of repertoire, scales, and exercise history to `~/violin/` without any privacy notice or confirmation. In context this is less dangerous than credential theft or exfiltration, but it still introduces unannounced local data persistence that could expose personal habits or learning records to other local users or future processes.

Vague Triggers

Medium

Confidence: 94% confidence
Finding: The logging triggers are broad enough that the skill may activate on casual mentions of practice, progress, or gaps in recent logs without a narrowly scoped user request. This can cause unintended prompting or data capture behavior, which is a real security and privacy concern even though the content is focused on violin practice rather than a sensitive domain.

Static analysis

No suspicious patterns detected.