Internet Explorer 9, Microsoft security issues: Microsoft fights back hacker attack flaw

If you use Internet Explorer, your computer may be at risk of a hacker attack.

Microsoft posted a security alert on its website late Monday night, warning about a flaw in its Internet Explorer 9 and earlier versions. Hundreds of millions of users may be affected.

Microsoft says hackers can exploit the security flaw when users visit a malicious website. Cyber crooks can gain access to personal information and take control of the PC.

Microsoft is working to fix the vulnerability, but users can install a temporary toolkit for free, which is available on Microsoft's website .