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Microsoft Windows DNSAPI.dll LLMNR Buffer Underrun DoS

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Microsoft Windows DNSAPI.dll LLMNR Buffer Underrun DoS



This module exploits a buffer underrun vulnerability in Microsoft's DNSAPI.dll as distributed with Windows Vista and later without KB2509553. By sending a specially crafted LLMNR query, containing a leading '.' character, an attacker can trigger stack exhaustion or potentially cause stack memory corruption. Although this vulnerability may lead to code execution, it has not been proven to be possible at the time of this writing. NOTE: In some circumstances, a '.' may be found before the top of the stack is reached. In these cases, this module may not be able to cause a crash.


  • jduck <jduck@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 auxiliary/dos/windows/llmnr/ms11_030_dnsapi
msf auxiliary(ms11_030_dnsapi) > show actions
msf auxiliary(ms11_030_dnsapi) > set ACTION < action-name >
msf auxiliary(ms11_030_dnsapi) > show options
    ...show and set options...
msf auxiliary(ms11_030_dnsapi) > run 

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