A static analyzer that compiles Skill instructions into code reached 95% recall, and 627 of 66,157 real ClawHub Skills were confirmed malicious
AspireAI community · arXiv
LLM-powered agents increasingly rely on third-party skills that combine natural-language instructions with executable code, creating supply-chain risks that span both artifacts, and rule-matching scanners cannot trace that cross-domain behavior. The Supply-Chain Scanner for Agent Skills compiles natural-language instructions into a constrained Python-style intermediate representation, builds program dependence graphs for instructions and bundled code, and connects them into a cross-domain graph where a Trust-Sensitivity-Capability model propagates security properties.
On a manually verified benchmark of 117 malicious and 117 benign skills, SCS reaches 85.6% average accuracy, 95.2% recall, and 86.9% F1 - the highest of the evaluated methods across five LLMs - with 80.2% precision. Analyzing 66,157 real-world ClawHub skills yields 2,473 candidates, of which 627 are confirmed malicious through dynamic validation and manual review.
The honest limit: precision sits at 80.2%, and confirming candidates required dynamic validation and manual review rather than the static analysis alone.
https://arxiv.org/abs/2610.33489
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