pkgutil --check-signature InstallMacOSHighSierra.pkg Look for:
http://dosdude1.com/highsierra/ 7. Verification (Security) After downloading, verify the PKG signature:
# Mount the DMG hdiutil attach InstallESD.dmg sudo dd if=/Volumes/OS\ X\ Install\ ESD/BaseSystem.dmg of=/dev/rdisk2 bs=1m
http://swcdn.apple.com/content/downloads/…/InstallMacOSHighSierra.pkg Exact link changes – use Mr. Macintosh’s current post for the live URL.