In an unprecedented move by a Chinese National Hacking Group, called Hafnium, hundreds of thousands of Exchange servers have been compromised, with over 30,000 accounts hacked this week. Leo says it's worse than that Russian Solar Winds attack. The hack takes advantage of a quartette of "zero-day exploits" that take advantage of bugs in Microsoft's Exchange email servers. Microsoft has put out an emergency update to plug the holes, and users are advised to install the fix immediately. Meanwhile, the efforts from the group have stepped up to try and glean as much information as possible before the holes are plugged.
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