Three gaps allowed an unverified binary to reach a trusted location:
- The ffmpeg ZIP fallback logged a warning on checksum mismatch and
installed anyway (the 7z path already aborted). Abort instead.
- The yt-dlp auto-update path downloaded and renamed the binary over
the verified one with no checksum at all. Verify against the official
SHA2-256SUMS like the first-install path, and use atomic os.replace.
- The yt-dlp first install streamed the download directly to the
trusted path and only verified afterwards; a crash in between left an
unverified executable to be run on next launch. Download to .part and
os.replace only after verification.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Jaroslav Beneš
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