By Johannes B. Ullrich, Ph.D. Guildma Malware is Now Using Facebook and YouTube as Update Channel
https://isc.sans.edu/forums/diary/Guildma+malware+is+now+accessing+Facebook+andYouTube+to+keep+uptodate/25222/
Supply Chain Issues: rest-client ruby gem backdoored
https://www.theregister.co.uk/2019/08/20/ruby_gem_hacked/
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