Microsoft has pointed the finger at three Chinese nation-state actors. Here's what we know, plus how to guard against future attacks.

The tech giants have evidence that Chinese hackers are exploiting the new bug, but warned "multiple actors" are also hacking into affected SharePoint systems.

The National Nuclear Security Administration, which oversees the design and upkeep of America’s nuclear weapons arsenal, was among those whose systems were breached as part of the recent Microsoft SharePoint hack.