Quote:Cybercriminals are now using compromised Microsoft Exchange servers as a foothold to deploy a new ransomware family called DearCry, Microsoft has warned.
 
The ransomware is the latest threat to beleaguer vulnerable Exchange servers, emerging shortly after Microsoft issued emergency patches in early March for four Microsoft Exchange flaws. The flaws can be chained together to create a pre-authentication remote code execution (RCE) exploit – meaning that attackers can take over servers without knowing any valid account credentials.
 
The flaws give attackers the opportunity to install a webshell for further exploitation within the environment — and now, researchers say attackers are downloading the new ransomware strain (a.k.a. Ransom:Win32/DoejoCrypt.A) as part of their post-exploitation activity on unpatched servers.
 
“We have detected and are now blocking a new family of ransomware being used after an initial compromise of unpatched on-premises Exchange Servers,” Microsoft said on Twitter, Thursday.