UK security officials have told companies here to install the latest Microsoft Exchange Server updates after hackers exploited flaws in the software to gain remote access to computers around the world.
Earlier this week Microsoft announced that Hafnium, a Chinese-sponsored hacker group, exploited vulnerabilities in Microsoft Exchange and left behind “web shells” that enabled the hackers to access victims’ systems remotely.
The attack impacted 30,000 companies in the USand hundreds of thousands of companies across the world.
Already, copycat hackers have started using the same vulnerability to plant ransomware on unsuspecting victims’ computers.
Yesterday, Microsoft saidt it had detected a new variety of ransomware, known as “DearCry”, which is designed specifically to target the Exchange Server vulnerability.
Microsoft has acted quickly to fix the breach. After issuing patches for the flaw the company took down a proof-of-concept tool to exploit the vulnerability which was published on Github, a repository for open-source code which Microsoft owns.