alt Hacker NewsYou can corroborate multiple trusted sources, especially those with histories. You can check the edit history of the Wikipedia article. Also, if you search "7zip" on HN, the second result with loads of votes and comments is 7-zip.org. Another is searching the Archlinux package repos; you can check the git history of the package build files to see where it's gotten the source from.
And we're really going to do all the brouhaha for a single dl of an alternative compressor ? And then multiple that work as a best practice for every single interaction on the Internet? No we're not.