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TypeScript toolchain security: keeping your build honest

2026-06-26 · DepSec Daily

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TypeScript's compiler is trustworthy; the exposure is the ecosystem around it — ts-node, loaders, and the thousands of @types/* packages you pull without reading.

Install

npm install -D typescript
npx tsc --init   # generates tsconfig.json

Where risk enters

  • @types/* packages are published by many different authors via DefinitelyTyped; a typosquatted or malicious types package is a real vector. Confirm the name maps to the library you use.
  • Loaders/runners (ts-node, SWC, esbuild plugins) execute code at build/run time — treat them as privileged.
  • tsconfig "extends" can pull a shared config from a package; that package is code you trust implicitly. Review it.

Verify before adding

npm view @types/node maintainers repository.url
osv-scanner --lockfile package-lock.json