Hacking Spree Feared After Breach of File-Sharing Software

Cybersecurity experts are bracing for a potential wave of extortion demands after a vulnerability was discovered in encrypted file-sharing software, a flaw that hackers have already used to target a string of high-profile victims, including British Airways and the BBC.

Several companies and a Canadian province said on Monday that they were dealing with breaches related to the secure file transfer product MOVEit from Progress Software Corp., according to statements from several of the affected entities. The vulnerability allowed hackers to steal files that companies had uploaded to MOVEit, according to Progress.

The flaw had prompted security alerts ...