A working exploit for the latest versions of Adobe’s PDF Reader software (X and XI) is being made available to malicious hackers for $50,000 via underground forums.

Starting with Version X, Adobe’s Reader software has employed a ‘sandbox’ that supposedly insulates the operating system from attacks originating in Reader content. The exploit code reportedly gets around the sandbox.

Adobe is investigating, but no patches are available yet. Since this threat is active, anyone using Adobe Reader X or XI should exercise extreme caution when opening PDF documents or clicking links to PDF documents from unknown sources. Another option is to uninstall the Adobe software and use an alternative like Foxit Reader.

More details from KrebsOnSecurity.