adversa.aiarticleπ‘οΈ SecurityAdversa AI tested eight open-source AI agent skill scanners (Cisco AI Defense skill-scanner, NVIDIA SkillSpector, mondoo skillcheck, skillcop, claude-skill-antivirus, huifer/skill-security-scan, ai-skill-scanner, hackmyagent) against a control-armed battery of real attacks on malicious Claude Code/agent SKILL.md files, and got a malicious skill past all eight β via paraphrase/translation of injection phrases, Unicode homoglyphs, encoding/reassembly tricks, a substring-allowlist bug in huifer, a hash-lookup-only client (mondoo) that fails open, and an unescaped LLM-judge prompt in skillcop that lets the skill's own text flip a CRITICAL verdict to clean. A parallel false-positive run on MalSkillBench (7,797 samples, 4,000 real benign skills) shows every scanner is either noisy (up to 62% FPR) or blind (recall as low as 0.28), and none beats an unconditional flag-everything F1 baseline; the piece closes with an 11-point "front end" spec (decode-then-rescan, Unicode-fold, canonicalize shell, resolve hosts not substrings, isolate LLM judges, report coverage) scanner builders should implement.
Claude CodeCisco AI DefenseNVIDIA SkillSpector+3
MalSkillBenchOASB leaderboardLD_PRELOAD+2
AI Security, Blue Team & DetectionΒ· Added 7 Oct 2026, published 30 Jul 2026