Improve MS15-034 DOS

[wchen-r7]

This improves the MS15-034 module to make the DOS more reliable. I only tested it on: Win 7 SP1 (IIS), and Windows 8.1 (IIS).

Verification

• Set up Windows 8.1 (32-bit), because this didn't seem to work well with the first release.
• Install IIS (from control panel)
• Win 8.1 automatically installs updates by default, so you will probably have to remove KB3042553 manually, and then turn off automatic update
• Start msfconsole
• use auxiliary/dos/http/ms15_034_ulonglongadd
• set rhosts [IP]
• set targeturi /iisstart.htm
• run to dos it
• It should crash (and restart)
• set targeturi /iis-85.png
• run again
• It should crash (and restart) again

[firefart]

@wchen-r7 another reference if you want to include it:
https://community.qualys.com/blogs/securitylabs/2015/04/20/ms15-034-analyze-and-remote-detection

[firefart]

And another one:
http://www.securitysift.com/an-analysis-of-ms15-034/

[bcook-r7]

Worked fine for me. Thanks!

Note: running 'check' causes this module to operate as a scanner rather than a DoS.