Six blue-chip stocks aggressively backed by Warren Buffett are on sale on Wall Street as the year draws to a close, mainly due to broad economic factors and stock market fashion. That makes them worth a look,

Despite once calling Apple the "best business" in the world, Buffett sold 100 million shares in the third quarter, cutting Berkshire's stake by 25%. And while Apple still ranked as the company's largest holding as of Sept. 30, Buffett has now sold more than 615 million shares in the last four quarters.

Nu Holdings (NYSE: NU), the parent company of digital banking giant Nubank, has seen its stock tumble 35% from its mid-November peak of $15.94.