Good morning. Microsoft says Chinese hackers exploited flaws in its software. Meme stock fever is spreading like it’s 2021. And heavy metal icon Ozzy Osbourne dies at age 76. Listen to the day’s top stories.

A newly discovered vulnerability in Microsoft’s SharePoint platform has spurred a mad frenzy from hackers — leading to breaches of some Microsoft clients.

Microsoft has accused Chinese state-sponsored groups of exploiting its SharePoint document management software to target users including large corporations and government agencies. The US software giant said on Tuesday that two groups — Linen Typhoon and Violet Typhoon — had exploited a so-called spoofing vulnerability to attack servers used by Microsoft customers.