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MS12-004 midiOutPlayNextPolyEvent Heap Overflow

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MS12-004 midiOutPlayNextPolyEvent Heap Overflow



This module exploits a heap overflow vulnerability in the Windows Multimedia Library (winmm.dll). The vulnerability occurs when parsing specially crafted MIDI files. Remote code execution can be achieved by using the Windows Media Player ActiveX control. Exploitation is done by supplying a specially crafted MIDI file with specific events, causing the offset calculation being higher than what is available on the heap (0x400 allocated by WINMM!winmmAlloc), and then allowing us to either "inc al" or "dec al" a byte. This can be used to corrupt an array (CImplAry) we setup, and force the browser to confuse types from tagVARIANT objects, which leverages remote code execution under the context of the user. Note: At this time, for IE 8 target, msvcrt ROP is used by default. However, if you know your target's patch level, you may also try the 'MSHTML' advanced option for an info leak based attack. Currently, this module only supports two MSHTML builds: 8.0.6001.18702, which is often seen in a newly installed XP SP3. Or 8.0.6001.19120, which is patch level before the MS12-004 fix. Also, based on our testing, the vulnerability does not seem to trigger when the victim machine is operated via rdesktop.


  • Shane Garrett
  • juan vazquez <juan.vazquez@metasploit.com>
  • sinn3r <sinn3r@metasploit.com>




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/ms12_004_midi
msf exploit(ms12_004_midi) > show targets
msf exploit(ms12_004_midi) > set TARGET < target-id >
msf exploit(ms12_004_midi) > show options
    ...show and set options...
msf exploit(ms12_004_midi) > exploit

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