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Rapid7

module

Sun Java Web Start Double Quote Injection

Disclosed
Oct 16, 2012
Created
May 30, 2018

Description

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
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.

Platform

Windows

Architectures

x86

Module Options

To display the available options, load the module within the Metasploit console and run the commands 'show options' or 'show advanced':


msf > use exploit/windows/browser/java_ws_double_quote
msf exploit(java_ws_double_quote) > show targets
...targets...
msf exploit(java_ws_double_quote) > set TARGET < target-id >
msf exploit(java_ws_double_quote) > show options
...show and set options...
msf exploit(java_ws_double_quote) > exploit

Title
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