Security firms are warning about new exploit code that targets a Microsoft Internet Explorer zero-day vulnerability, enabling attackers to take complete control of a vulnerable system.
The vulnerability could be used by attackers in drive-by attacks. The new flaw was reported by French Security firm VUPEN Security Dec. 9 and affects Internet Explorer 6, 7 and 8 running on Windows XP, Windows Vista and Windows 7.
VUPEN gave the vulnerability a "critical" rating. The browser contains a flaw which causes a memory error in Internet Explorer's HTML parsing engine when it processes Cascading Style Sheet (CSS) import rules in a Web page, according to the VUPEN advisory. Attackers can set up a malicious Web page or inject code into vulnerable websites to target the flaw.
The vulnerability was added Wednesday as an exploit to the Metasploit Framework.
Microsoft blocked five critical vulnerabilities in Internet Explorer in its December round of monthly patches. Some of the flaws patched by Microsoft were being used by attackers in drive-by attacks.