Check Point Research tracked a tenfold increase in attempts to exploit vulnerable on-premises Microsoft Exchange servers. The global exploits of four vulnerabilities in Exchange servers grew from an estimated 700 on Thursday to about 7,200 on Monday. Some 23% of all attacks were aimed at the government/military sector, followed by manufacturing, finance/banking, software vendors and healthcare. Microsoft has released an interim mitigation tool that allows them to take quick action to prevent attacks that exploit the unpatched ProxyLogon flaw.”]
Source: https://www.cuinfosecurity.com/microsoft-exchange-server-attack-attempts-skyrocket-a-16194