Recently, RealPlayer has shown to have vulnerabilities in its software that may allow hackers to spread spyware through it. For example, 24/7 Media, a top online advertisement company, had its server compromised by having hackers spread spyware and pop-ups to its visitors. The hackers created malicious files in the form of e-mail attachments.
Mac and Linux computers are not protected from this RealPlayer vulnerability. Any computer with RealPlayer installed on it 
must be protected from this hacking potential.
You can protect yourself from such malware by updating RealPlayer to the latest updates.
Please make sure that whatever your operating system, you install the latest updates as this can be automated and save you a lot of time and aggravation.