Tuesday, February 9, 2010

More details on MS10-006

An Advisory as been released by Microsoft patching MS10-006.
This vulnerability as been found back in november while testing some client side vulnerability on SMB.
A full advisory regarding the details of this issue is located here

Regarding the SRD statement for smb client possible exploitation i'd like to add & post a small tool abusing netbios name service functionnality.
Ronald Bowes did some great work with nbtool for such purpose.

You can find a small version in python here;

Basicly, anyone on the segment using :
net use \\blabla\share
net view \\blabla\share
dir \\blabla\share
etc
On vista/7/server2008|R2 it's also possible to use start -> search box --> \\existing_machine\share

Any of these command result in a NBNS query asking which IP is using this netbios name
Then this small utility will answer it's at "attacker_IP".
Once the ip resolved, the machine will initiate a smb connection to that IP.
You can also abuse the BROWSER service for same kind of purpose, I will post a full entry when i get some free time ...