Microsoft issued a security advisory late Tuesday that malicious attackers are targeting versions of its Office Excel with vulnerabilities.
Microsoft Office Excel 2003 with Service Pack 2; Excel Viewer 2003; Excel 2002; Excel 2000; and Microsoft Excel 2004 for the Mac are affected by the security vulnerabilities, according to the advisory.
People who open a malicious e-mail attachment or visit a malicious Web site may find that their systems are compromised and that arbitrary remote code is executed. Computers configured to allow the user to have administrative user rights are at greater risk that those with few user rights on the system.
Microsoft said it is still investigating the security vulnerabilities but noted the attacks appear to be targeted and not widespread, according to its security blog.