Vulnetix Typosquat Check Skill

Use when

• Onboarding: scan all installed deps for typosquat/malware matches.
• Vetting a single package that looks suspicious (react-utill, lodash-utility, etc.).
• CI gate: block any installed dep flagged BLOCK.
• Post-incident: cross-reference your installed deps against newly-discovered malware families.
• Investigating a single package after a vendor advisory mentions name-similarity attacks.

Don't use for

• CVE-based vulnerability scanning — use vulnetix scan --sca.
• Generic package risk before adding — use dependency-choice.
• Detecting compromised packages via runtime behaviour — Pix is static-only.

Conventions

Follows skills/_lib/contract.md. In short: use the vulnetix_* MCP tools when the agent has them and the CLI otherwise — both shape their own output, so there is no jq step any more. Independent calls go out as concurrent Bash tool calls in one message. One trailing suggestion, not a playbook. See the contract for surface selection, output style and memory writes.

Step 1: Decide mode

• Single-package: $ARGUMENTS is a name → check just that.
• --installed: read lockfile (per derived.primary_package_manager), check every direct dep.

Step 2: Run gated scan + AI-malware lookup

vulnetix scan --block-malware -o json
vulnetix vdb ai-malware list -o json
vulnetix vdb packages search "$PACKAGE" --ecosystem "$ECO" -o json   # for similarity hits

The packages search response includes typosquat-similarity scores against well-known package names.

Step 3: Render

| Package | Version | Verdict | Reason |
| react-utill | 1.0.0 | BLOCK | typosquat of react-util (similarity 0.92), 0 stars, 14d old |

Verdicts: ALLOW / WARN / BLOCK.

Step 4: Memory + .gitignore note

Append event: typosquat-check with verdicts to memory. If any BLOCK, surface a strong suggestion to remove the package and check git history (git log -p -- <package-manifest-path>).

Edge cases & gotchas

• Similarity scoring is heuristic (Levenshtein + popularity weighting). Borderline names need human review.
• --installed mode reads the lockfile per derived.primary_package_manager — make sure the lockfile is up-to-date.
• vdb ai-malware list --package <name> returns matches across ecosystems; filter by --ecosystem for accuracy.
• BLOCK verdict is rare and high-signal; treat as urgent. Most flagged packages are WARN (borderline name + low maintainer signal).
• Removing a flagged package is destructive — review git log -p -- <manifest> BEFORE deletion to understand what code depends on it.
• False positives: legitimate packages with similar names to popular ones (e.g. typescript-eslint vs typescript) can score high — manual triage needed.