Re: Authentication flaw in microsoft SMB protocol

[Dave Aitel <dave () immunitysec com>]

Also found and demonstrated by dildog at defcon 3 years ago. So don't
hold your breath waiting for that patch.

Dave Aitel
Immunity, Inc.
http://www.immunitysec.com/ 

On 19 Apr 2003 13:24:33 -0000
<seclab () ce aut ac ir> wrote:

> Detailed information:
> http://seclab.ce.aut.ac.ir/vreport.htm
>
> Summary
> =======
> Microsoft uses SMB Protocol for “File and Printer sharing service” in
> all versions of Windows. Upon accessing a network resource, NTLM 
> Authentication is used to authenticate the client on the server. When
> a logged-in user requests for a network share on the server, Windows 
> automatically sends the encrypted hashed password of the logged-in 
> username to the target SMB server before prompting for password.
> Although the hashed password is not sent in plaintext format, and it
> is encrypted by the server challenge, a malicious SMB Server could use
> this information to authenticate on the client machine and in many
> cases, gain full control over the shared objects of the client such as
> C$, etc.
...
> Exploit
> =======
> We will publish the exploit code after a patch be created by software 
> vendor.