Seven-tier security audit of the main process, each finding fixed with a
regression test. Typecheck (node + web) clean; unit tests 106 -> 140.
- Tier 1 (command exec/argv): allowlist the yt-dlp --update-to channel
(blocks arbitrary-binary-install RCE); gate per-download extraArgs behind
the customCommandEnabled consent flag in main (blocks --exec RCE); resolve
taskkill/schtasks by absolute System32 path; validate per-download
outputDir; normalize the URL in assertHttpUrl and use it at every spawn.
- Tier 2 (input validation): fix isSafeFilenameTemplate drive-relative
('C:foo') and Windows dotted-'..' traversal bypasses; percent-encode the
untrusted id in entryUrl; catch reserved device names with extensions in
sanitizeDirSegment.
- Tier 3 (fs/backup): drop malformed template rows in importBackup;
normalize deep-link URLs via assertHttpUrl.
- Tier 4 (cookies): confine the sign-in window's navigations/popups to web
URLs (recursively) and deny all web permissions on its session.
- Tier 5 (deep-link/argv): bound the .url file read to 64 KB; match the
aerofetch:// scheme case-insensitively.
- Tier 6 (Electron window): deny camera/mic/geolocation/USB/HID/serial/
Bluetooth permissions on the app window.
- Tier 7 (network/persistence): restrict the watched-source RSS fetch to
youtube.com feed URLs (SSRF guard); complete isValidSource validation.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Security:
- S1 (backup.ts): require explicit confirmation before enabling custom-command
templates from a backup file; import templates in a disabled state if declined
- S2 (cookies.ts): deny non-http/https popups in cookie login window, matching
the main window's setWindowOpenHandler defence
- S3 (download.ts): main-process concurrency cap — startDownload now rejects
spawns when active.size >= maxConcurrent (defence-in-depth; renderer already
enforces this but should not be the only gate)
- S4 (settings.ts, validation.ts): reject filenameTemplate values containing
path traversal (.. segments or absolute paths); validate outputDir is absolute
- S5 (history.ts, errorlog.ts, templates.ts, validation.ts): per-field
validation on JSON reads — invalid entries dropped rather than blindly trusted
Performance:
- P1 (settings.ts): getSettings() now only writes to disk when sanitization
actually changed a value; removes synchronous file I/O on every hot-path read
- P2 (ipc.ts, download.ts, downloads.ts): renderer forwards its pre-probed
metadata (title/channel/duration) via StartDownloadOptions.meta; main uses
it directly instead of spawning a redundant second yt-dlp probe
Maintainability:
- M1 (log.ts, download.ts, probe.ts): extract duplicated cleanError() to
src/main/log.ts; both callers import from the shared module
- M2 (buildArgs.ts): document parseExtraArgs escape-sequence limitations
- M3 (electron-builder.yml): clarify icon TODO as a pre-release action
- P3 (downloads.ts): document that lowering maxConcurrent mid-flight does
not pause active downloads (intended behaviour, now written down)
Tests:
- Add test/validation.test.ts covering isSafeFilenameTemplate, isSafeOutputDir,
isValidHistoryEntry, isValidErrorLogEntry, isTemplateLike (76 tests pass)
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
debont80