Hackers linked to China used a zero-day vulnerability in Microsoft s Internet Explorer browser to compromise corporate systems at more than 30 U.S. companies. The vulnerability is still unpatched and can lead to remote code execution attacks if a target is lured to a booby-trapped Web site or views a malicious online advertisement. The flaw affects Internet Explorer 6 Service Pack 1 on Microsoft Windows 2000 Service Pack 4. Microsoft is considering an out-of-band emergency IE patch to fix this vulnerability.
Source: https://threatpost.com/microsoft-confirms-ie-zero-day-used-google-attack-011610/73379/