VSIX fetch + extract for URL targets now runs in a sub-process wrapped by
sandbox-exec (macOS) or bwrap (Linux), reusing the same primitives proven
by the v5.1 git-clone sandbox. Defense-in-depth — even if our own
zip-extract.mjs ever has a bypass, the kernel refuses any write outside
the per-scan temp directory.
New files:
- scanners/lib/vsix-fetch-worker.mjs — sub-process worker. Argv: --url
--tmpdir; emits one JSON line on stdout (ok/sha256/size/source/extRoot
or ok:false/error/code). Silent on stderr. Exit 0/1.
- scanners/lib/vsix-sandbox.mjs — wrapper. Exports buildSandboxProfile,
buildBwrapArgs, buildSandboxedWorker, runVsixWorker. 35s timeout, 1 MB
stdout cap.
Changes:
- scanners/ide-extension-scanner.mjs: fetchAndExtractVsixUrl is now
sandbox-aware (useSandbox option, default true). In-process logic
preserved as fallback. New meta.source.sandbox field:
'sandbox-exec' | 'bwrap' | 'none' | 'in-process'.
- scan(target, { useSandbox }) defaults to true; tests pass false because
globalThis.fetch mocks do not cross process boundaries.
- Windows fallback: in-process with meta.warnings advisory.
Tests:
- 8 new tests in tests/scanners/vsix-sandbox.test.mjs (per-platform
profile generation, worker arg construction, live worker exit
behavior on invalid URLs — no network).
- Existing URL tests updated to opt out of sandbox (useSandbox: false).
- 1344 → 1352 tests, all green.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Pre-installation verification of VS Code extensions via URL — fetch a remote
VSIX, extract it in a hardened sandbox, and run the existing IDE scanner
pipeline against it. No npm dependencies.
Sources:
- VS Code Marketplace (publisher.gallery.vsassets.io direct download)
- OpenVSX (open-vsx.org official API)
- Direct .vsix HTTPS URLs
Defenses:
- HTTPS-only, TLS verified, manual redirect with per-source host whitelist
- 30s total timeout via AbortController
- 50MB compressed cap, 500MB uncompressed, 100x expansion ratio
- Zero-dep ZIP extractor: zip-slip, absolute paths, drive letters, NUL bytes,
symlinks (Unix mode 0xA000), depth limits, ZIP64 rejected, encrypted rejected
- SHA-256 streamed during fetch, surfaced in meta.source
- Temp dir cleanup in all paths (try/finally)
Files:
- scanners/lib/vsix-fetch.mjs (HTTPS fetcher, host whitelist, streaming SHA-256)
- scanners/lib/zip-extract.mjs (zero-dep parser with hardening caps)
- knowledge/marketplace-api-notes.md (endpoint reference)
- 3 test files (48 tests added: vsix-fetch, zip-extract, ide-extension-url)
Tests: 1296 → 1344 (all green).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
