This module exploits a flaw in the Web Start component of the Sun Java Runtime Environment. Parameters initial-heap-size and max-heap-size in a JNLP file can contain a double quote which is not properly sanitized when creating the command line for javaw.exe. This allows the injection of the -XXaltjvm option to load a jvm.dll from a remote UNC path into the java process. Thus an attacker can execute arbitrary code in the context of a browser user. This flaw was fixed in Oct. 2012 and affects JRE <= 1.6.35 and <= 1.7.07. In order for this module to work, it must be run as root on a server that does not serve SMB (In most cases, this means non-Windows hosts). Additionally, the target host must have the WebClient service (WebDAV Mini-Redirector) enabled. Alternatively, a UNC path containing a jvm.dll can be specified, bypassing the Windows limitation for the Metasploit host.
To display the available options, load the module within the Metasploit console and run the commands 'show options' or 'show advanced':
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– Jim O’Gorman | President, Offensive Security