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Security audit

Skills Builder

Security checks for vulnerabilities and agentic risk

Overview

This is a plain Markdown helper for drafting user-reviewed Skills, with no executable code, network access, credential use, or hidden persistence.

Before installing or using generated Skills, review the trigger phrases, off-limits rules, and any text extracted from prior conversation. Remove sensitive details and avoid rules that suppress important safety warnings or make the assistant follow unsafe instructions.

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
  • Prompt InjectionInstruction Override, Hidden Instructions, Exfiltration Commands
  • Excessive AgencyUnrestricted Tool Access, Autonomous Decision Making, Scope Creep
  • Trigger AbuseOverly Broad Trigger, Shadow Command Trigger, Keyword Baiting Trigger
  • Data ExfiltrationExternal Transmission, Env Variable Harvesting, File System Enumeration
  • Privilege EscalationExcessive Permissions, Sudo/Root Execution, Credential Access
Findings (8)

Anti-Refusal Statement

High
Category
Anti-Refusal
Confidence
70% confidence
Finding

Skill instructs the agent to never refuse or to always comply. Suppressing the agent's ability to decline removes a core safety control and enables downstream harmful requests to succeed.

Content

Scanner excerpt · SKILL.md (reported line 34)May include surrounding context.

md
> "It sounds like you want me to automatically help you with [some task] in [some situation]. Did I get that right?"

If the user is vague (e.g. "I want to create a Skill"), use this prompt:
> "Got it! First, tell me — is there something you **do repeatedly** where you have to re-explain the rules to me every time? Or is there a way I've responded that you really liked, and you wish I'd always respond like that?"

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Anti-Refusal Statement

High
Category
Anti-Refusal
Confidence
80% confidence
Finding

Skill instructs the agent to omit warnings, disclaimers, or ethical commentary. Stripping safety caveats hides risk from the user and is a common jailbreak preamble.

Content

Scanner excerpt · SKILL.md (reported line 63)May include surrounding context.

md
> For example: no technical jargon? No disclaimers? Don't ask too many follow-up questions?"

Ae1

High
Category
analysis-evasion
Confidence
100% confidence
Finding

Referenced artifact was not completely inspected

Content

Scanner excerpt · SKILL.md (reported line 158)May include surrounding context.

md
1. The finished `SKILL.md` file (downloadable)

Vague Triggers

High
Category
Not specified by scanner
Confidence
97% confidence
Finding

The listed trigger phrases are broad, natural-language requests such as 'I want to create a Skill' and 'customize how you respond to me,' which can plausibly occur in ordinary conversations unrelated to intentional skill use. This creates a real risk of unintended activation, causing the skill to override normal assistant behavior in contexts where the user did not mean to invoke it.

Content

No source excerpt is available for this finding.

Anti-Refusal Statement

High
Category
Anti-Refusal
Confidence
80% confidence
Finding

Skill instructs the agent to omit warnings, disclaimers, or ethical commentary. Stripping safety caveats hides risk from the user and is a common jailbreak preamble.

Content

Scanner excerpt · quality_checklist.md (reported line 37)May include surrounding context.

md
- [ ] Prohibitions are specific (e.g., "Never add disclaimers" not "Be careful")

Missing User Warnings

Medium
Category
Not specified by scanner
Confidence
91% confidence
Finding

The skill tells the assistant to automatically generate a finished, downloadable SKILL.md on the user's behalf without any explicit user-facing notice about content creation or verification. This can cause users to accept generated instructions as if they were validated artifacts, increasing the risk of unsafe, overbroad, or privacy-invasive skill behavior being produced and reused.

Content

No source excerpt is available for this finding.

Missing User Warnings

Medium
Category
Not specified by scanner
Confidence
95% confidence
Finding

The skill instructs the assistant to 'look back at our conversation' and automatically extract rules from chat history without first warning the user that prior messages may be analyzed for this purpose. That creates a privacy and consent issue because sensitive details from earlier conversation could be incorporated into the generated skill unexpectedly.

Content

No source excerpt is available for this finding.

Autonomous Decision Making

Medium
Category
Excessive Agency
Confidence
75% confidence
Finding

Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.

Content

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

md
- [ ] Terminology and domain-specific language is correctly used for the target field
- [ ] Rules are written in plain, direct language (imperative form preferred: "Use X", "Avoid Y")

**Self-check question:** Could Claude follow every rule without asking for clarification?

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Static analysis

No suspicious patterns detected.