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Sendmail SMTP Address prescan Memory Corruption

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Sendmail SMTP Address prescan Memory Corruption



This is a proof of concept denial of service module for Sendmail versions 8.12.8 and earlier. The vulnerability is within the prescan() method when parsing SMTP headers. Due to the prescan function, only 0x5c and 0x00 bytes can be used, limiting the likelihood for arbitrary code execution.


  • aushack <patrick@osisecurity.com.au>


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/smtp/sendmail_prescan
msf auxiliary(sendmail_prescan) > show actions
msf auxiliary(sendmail_prescan) > set ACTION < action-name >
msf auxiliary(sendmail_prescan) > show options
    ...show and set options...
msf auxiliary(sendmail_prescan) > run 

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