PDF files are often used for exchanging documents between corporations and individuals, and have been considered quite secure regarding the potential to contain malicious program code.

However, critical vulnerabilities have again been identified in Adobe Reader and Adobe Acrobat. These vulernabilities could allow an attacker to take control of the affected system. Exploit code utilizing the vulnerabilities is reported being used by the infamous malware Tibs/Storm.

Adobe has published an update that resolves these vulnerabilities (and fixes other errors). More information in Abobe's Security bulletin where there are also links to downloading the latest version

Norman advices all affected users to update to  Adobe Reader 8.1.2 or Acrobat 8.1.2.