Rapid7 Vulnerability & Exploit Database

MS11-050 IE mshtml!CObjectElement Use After Free

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MS11-050 IE mshtml!CObjectElement Use After Free



This module exploits a use-after-free vulnerability in Internet Explorer. The vulnerability occurs when an invalid tag exists and other elements overlap/cover where the object tag should be when rendered (due to their styles/positioning). The mshtml!CObjectElement is then freed from memory because it is invalid. However, the mshtml!CDisplay object for the page continues to keep a reference to the freed and attempts to call a function on it, leading to the use-after-free. Please note that for IE 8 targets, JRE (Java Runtime Environment) is required to bypass DEP (Data Execution Prevention).


  • d0c_s4vage
  • sinn3r <sinn3r@metasploit.com>
  • bannedit <bannedit@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/ms11_050_mshtml_cobjectelement
msf exploit(ms11_050_mshtml_cobjectelement) > show targets
msf exploit(ms11_050_mshtml_cobjectelement) > set TARGET < target-id >
msf exploit(ms11_050_mshtml_cobjectelement) > show options
    ...show and set options...
msf exploit(ms11_050_mshtml_cobjectelement) > exploit

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