Computer users in China and Korea were the hardest hit by the latest wave of zero-day malware attacks targeting a flaw in the Internet Explorer browser, according to data released by the Microsoft Malware Protection Center (MMPC).
The attacks, first spotted on March 9, included Trojan downloaders and backdoor programs that gave malicious hackers full access to hijacked PCs.
According to the MMPC, the targets have spanned over 50 countries, with the most frequently targeted computers in China and Korea, with the US trailing a distant third place. This chart provides a visual breakdown of the compromised computers:
The MMPC said the attack landscape escalated immediately after proof-of-concept come was released and fitted into public exploit testing tool like Metasploit.
Unprotected users are susceptible to infection when they browse to a malicious Web page that attempts to exploit this vulnerability. If the exploit is successful, a number of malware families may be installed on the victim’s computer. The majority of malware downloaded after a successful exploit are trojans.
The group listed at least six Trojan variants related to these attacks and said it expects the threat landscape to mellow with the release and adoption of the just-released emergency IE patch.