Back to skill

Security audit

Grill Skill

Security checks across malware telemetry and agentic risk

Overview

This skill is a disclosed eval-building workflow that writes and runs skill evaluation files, with no evidence of hidden, deceptive, or unrelated behavior.

Install this if you want an agent to help create and run evals for skills. Be aware it can write .eval.yaml files beside a skill and run Caliper/agent CLI commands, so review proposed eval content before confirming writes or runs.

SkillSpector

By NVIDIA
Vulnerability Patterns
  • Excessive AgencyUnrestricted Tool Access, Autonomous Decision Making, Scope Creep
  • Tool MisuseTool Parameter Abuse, Chaining Abuse, Unsafe Defaults
  • 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 (10)

Autonomous Decision Making

Medium
Category
Excessive Agency
Content
the SKILL.md, gives some understanding of the skill, and asks the user for
      input before generating anything — then STOPS to wait. The number of
      questions does not matter. Fail if the agent skips the interview: it
      invents the user's answers, generates the eval tasks itself without
      asking, or writes any .eval.yaml file in this turn.
    assert: |
      import glob
Confidence
75% confidence
Finding
without asking

Tool Parameter Abuse

High
Category
Tool Misuse
Content
# a deterministic guard that it did NOT fabricate answers and write a spec.
  - name: Interviews before generating — asks, then stops (does not run ahead)
    setup: |
      rm -rf /tmp/grill-fresh
      mkdir -p /tmp/grill-fresh
      cat > /tmp/grill-fresh/SKILL.md << 'EOF'
      ---
Confidence
90% confidence
Finding
rm -rf /tmp/grill-fresh mkdir -p /tmp/grill-fresh cat > /tmp/grill-fresh/SKILL.md << 'EOF' --- name: changelog-writer description: Use when the user wants to turn merged

Tool Parameter Abuse

High
Category
Tool Misuse
Content
# existing spec was left untouched in this first turn.
  - name: Detects an existing eval and asks before touching it
    setup: |
      rm -rf /tmp/grill-existing
      mkdir -p /tmp/grill-existing
      cat > /tmp/grill-existing/SKILL.md << 'EOF'
      ---
Confidence
90% confidence
Finding
rm -rf /tmp/grill-existing mkdir -p /tmp/grill-existing cat > /tmp/grill-existing/SKILL.md << 'EOF' --- name: summarize description: Use when the user wants to summarize

Tool Parameter Abuse

High
Category
Tool Misuse
Content
# workflow and the one task with a full artifact assert.
  - name: Serializes a valid 3-task spec when the structure is given
    setup: |
      rm -rf /tmp/grill-serialize
      mkdir -p /tmp/grill-serialize
      cat > /tmp/grill-serialize/SKILL.md << 'EOF'
      ---
Confidence
90% confidence
Finding
rm -rf /tmp/grill-serialize mkdir -p /tmp/grill-serialize cat > /tmp/grill-serialize/SKILL.md << 'EOF' --- name: hello-file description: Use when the user wants to write

Tool Parameter Abuse

High
Category
Tool Misuse
Content
# a deterministic guard that it did NOT fabricate answers and write a spec.
  - name: Interviews before generating — asks, then stops (does not run ahead)
    setup: |
      rm -rf /tmp/grill-fresh
      mkdir -p /tmp/grill-fresh
      cat > /tmp/grill-fresh/SKILL.md << 'EOF'
      ---
Confidence
85% confidence
Finding
rm -rf /tmp/

Tool Parameter Abuse

High
Category
Tool Misuse
Content
Read the merged PRs since the last tag and write a grouped changelog
      entry (Features / Fixes / Chore) to CHANGELOG.md.
      EOF
    cleanup: rm -rf /tmp/grill-fresh
    prompt: >
      I want to create a caliper eval for my skill at
      /tmp/grill-fresh/SKILL.md. I'm here and will answer whatever you need —
Confidence
85% confidence
Finding
rm -rf /tmp/

Tool Parameter Abuse

High
Category
Tool Misuse
Content
# existing spec was left untouched in this first turn.
  - name: Detects an existing eval and asks before touching it
    setup: |
      rm -rf /tmp/grill-existing
      mkdir -p /tmp/grill-existing
      cat > /tmp/grill-existing/SKILL.md << 'EOF'
      ---
Confidence
85% confidence
Finding
rm -rf /tmp/

Tool Parameter Abuse

High
Category
Tool Misuse
Content
prompt: Summarize /tmp/notes.txt
          expect: The agent produces a summary of the file contents.
      EOF
    cleanup: rm -rf /tmp/grill-existing
    prompt: >
      I want to improve the eval for my skill at
      /tmp/grill-existing/SKILL.md using grill-skill. I'm here to answer your
Confidence
85% confidence
Finding
rm -rf /tmp/

Tool Parameter Abuse

High
Category
Tool Misuse
Content
# workflow and the one task with a full artifact assert.
  - name: Serializes a valid 3-task spec when the structure is given
    setup: |
      rm -rf /tmp/grill-serialize
      mkdir -p /tmp/grill-serialize
      cat > /tmp/grill-serialize/SKILL.md << 'EOF'
      ---
Confidence
85% confidence
Finding
rm -rf /tmp/

Tool Parameter Abuse

High
Category
Tool Misuse
Content
Write the text "hello world" to /tmp/hello.txt when the user asks.
      EOF
    cleanup: rm -rf /tmp/grill-serialize
    prompt: >
      Write the file directly now — do NOT ask me any clarifying questions
      first; I have given you everything you need. Use the grill-skill to write
Confidence
85% confidence
Finding
rm -rf /tmp/

VirusTotal

64/64 vendors flagged this skill as clean.

View on VirusTotal

Static analysis

No suspicious patterns detected.