Over 900 servers have been hacked thanks to a Zimbra zero-day

Zimbra Collaboration Suite carried a zero-day vulnerability for more than a month, presenting hackers with a real field day that resulted in almost 900 servers (opens in new tab) being  hacked. 

Researchers at Kaspersky noted the vulnerability being reported on the Zimbra forum, after which all kinds of advanced persistent threat (APT) groups leveraged it to compromise countless servers. 

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