Package integrity checks now catch tampering via file permissions and hard links, not just size or symlinks
When Claude Code verifies the integrity of an extracted package, it now opens each file or directory with a flag that refuses to follow symbolic links, checks that files have exactly one hard link, and strips any group- or world-writable permission bits it finds. The directory-walk integrity check now flags a result as 'tampered' if a file isn't a plain file or fails this new permission check, in addition to the existing 'oversize', 'symlink', and 'reserved' failure outcomes.
This closes off ways a malicious or corrupted package could exploit file permissions, hard links, or symlink tricks during extraction, giving Claude Code a stronger guarantee that extracted files match what was intended.