The disclaimer on the Duffel Blog website says that it is an untrustworthy website and consequently the news about the Pentagon being hacked is false.
The news originated on the Duffel Blog website. We verified the credibility of the article on the website by checking the 'about us' section. The disclaimer stated that it is not responsible for incorrect and inaccurate information given in the published articles as it was classified as satire and any resemblance to real persons, living or dead, or actual military units and companies is purely coincidental. All characters appearing in the articles on the website are entirely fictional. Hence, we conclude that China hacked the Pentagon to ensure only incompetent officers get promoted is a piece of fake news.