Naked short selling can be used to manipulate the price of securities by driving their price down, and its use in this way is illegal, however, the practice is considered benign under certain circumstances, such as trading by market makers.
In the United States, naked short selling is covered by various SEC regulations which prohibit the practice. With some corrupt entities that we have in the market these days, I wouldn't be surprised if this happened, though they would be taking a big chance and risking jail time by doing so.