Rapid7

module

Windows IIS HTTP Protocol Stack DOS

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Disclosed
May 11, 2021
Created
Mar 17, 2022

Description

This module exploits CVE-2021-31166, a UAF bug in http.sys
when parsing specially crafted Accept-Encoding headers
that was patched by Microsoft in May 2021, on vulnerable
IIS servers. Successful exploitation will result in
the target computer BSOD'ing before subsequently rebooting.
Note that the target IIS server may or may not come back up,
this depends on the target's settings as to whether IIS
is configured to start on reboot.

Authors

Max
Stefan Blair
Axel Souchet
Maurice LAMBERT [email protected]

Platform

Windows

References

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/http/http_sys_accept_encoding_dos_cve_2021_31166
    msf auxiliary(http_sys_accept_encoding_dos_cve_2021_31166) > show actions
        ...actions...
    msf auxiliary(http_sys_accept_encoding_dos_cve_2021_31166) > set ACTION < action-name >
    msf auxiliary(http_sys_accept_encoding_dos_cve_2021_31166) > show options
        ...show and set options...
    msf auxiliary(http_sys_accept_encoding_dos_cve_2021_31166) > run
Title
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