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RE: Passwords with Lan Manager (LM) under Windows
From: "Craig Wright" <cwright () bdosyd com au>
Date: Thu, 22 Sep 2005 19:40:51 +1000

Hi
 
And what I said the first time was IPSec with Kerberos.
A security association between two devices is set up by the AH protocol 
 
Security Associations: A Security Association (SA) is a set of security information that describes a particular kind of 
secure connection between one device and another. You can consider it a "contract", if you will, that specifies the 
particular security mechanisms that are used for secure communications between the two.
A device's security associations are contained in its Security Association Database (SAD)
 
authenticate 
 // (say aw'thentuhkayt) verb (t) (authenticated; authenticating) 1. to make authoritative or valid. 2. to establish as 
genuine.
--authenticable // (say aw'thentikuhbuhl), adjective
--authentication // (say aw.thentuh'kayshuhn), noun
--authenticator, noun 
 
http://www.ietf.org/rfc/rfc2401.txt (RFCs 2401,2402,2406,2408,2409 all cover this)
Goals/Objectives/Requirements/Problem Description

   IPsec is designed to provide interoperable, high quality, cryptographically-based security for IPv4 and IPv6.  The 
set of security services offered includes access control, connectionless integrity, data origin authentication, 
protection against replays (a form of partial sequence integrity), confidentiality (encryption), and limited traffic 
flow confidentiality.  These services are provided at the IP layer, offering protection for IP and/or upper layer 
protocols
 
Please note that this is NOT out of context and that a goal of IPSec **IS** "data origin authentication"
 
And not to just google a few areas
 
http://www.microsoft.com/windows2000/techinfo/planning/security/ipsecsteps.asp
Internet Protocol Security (IPSec) provides application-transparent encryption services for IP network traffic as well 
as other network access protections for the Windows 2000 operating system.
 
and
Using Internet Protocol Security (IPSec), you can provide data privacy, integrity, authenticity, and anti-replay 
protection for network traffic in the following scenarios:

*       Provide for end-to-end security from client-to-server, server-to-server, and client-to-client using IPSec 
transport mode. 
*       Secure remote access from client-to-gateway over the Internet using Layer Two Tunneling Protocol (L2TP) secured 
by IPSec. 

Yes there are 2 senarios - L2TP is ONE of them. I was and am refering to point 1.

"IPSec provides secure gateway-to-gateway connections across outsourced private wide area network (WAN) or 
Internet-based connections using L2TP/IPSec tunnels or pure IPSec tunnel mode. IPSec tunnel mode is not designed to be 
used for virtual private network (VPN) remote access. The Windows 2000 Server operating system simplifies deployment 
and management of network security with Windows 2000 IP Security, a robust implementation of IP Security (IPSec). 
Designed by the Internet Engineering Task Force (IETF) as the security architecture for the Internet Protocol (IP), 
IPSec defines IP packet formats and related infrastructure to provide end-to-end strong authentication, integrity, 
anti-replay, and (optionally) confidentiality for network traffic. An on-demand security negotiation and automatic key 
management service is also provided using the IETF-defined Internet Key Exchange (IKE), RFC 2409. IPSec and related 
services in Windows 2000 have been jointly developed by Microsoft and Cisco Systems, Inc."

Again please note "to provide end-to-end strong authentication"

If you prefer a source other than the IEFT or MSFT

http://www.windowsecurity.com/articles/Securing_Data_in_Transit_with_IPSec.html

"What IPSec Does
IPSec is designed to provide authentication (verification of the identity of the sender), integrity (assurance that the 
data was not changed in transit) and confidentiality (encryption of the data so that it can’t be read by anyone who 
doesn’t have the correct key)."

As for "article you reference does indeed use the phrase "IPSec Authentication," but as any who reads it
will see, the term is used to describe the higher level protocol deployment; a higher level protocol that has, as I 
said before, 3 authentication mechanisms available to establish a connection.  Here's the article that should be
referenced:"
 
Well actually - the article ***I*** used is above and referenced. I also used
http://support.microsoft.com/Default.aspx?kbid=253169
http://support.microsoft.com/support/kb/articles/Q254/9/49.ASP
http://support.microsoft.com/Default.aspx?kbid=254949
http://www.securityfocus.com/infocus/1526
http://www.microsoft.com/technet/itsolutions/network/security/ipsecld.mspx
http://www.microsoft.com/technet/prodtechnol/windowsserver2003/library/ServerHelp/d3e4d311-32eb-4954-9cd8-6d03e4d63e53.mspx
http://www.windowsitpro.com/WindowsSecurity/Article/ArticleID/25730/25730.html
and a few RFC's - to which for the record - I prefer altavista over google.
 
"Using IPSec to Lock Down a Server" from the above list is old but goode
 
Please if you wish to have have me take something off the list, Please ask off the list
 
Craig

        -----Original Message----- 
        From: Thor (Hammer of God) [mailto:thor () hammerofgod com] 
        Sent: Thu 22/09/2005 5:54 PM 
        To: Craig Wright; pand0ra.usa () gmail com; pen-test () securityfocus com 
        Cc: 
        Subject: Re: Passwords with Lan Manager (LM) under Windows
        
I saw this one first, so I go top-down (It's getting late for me, so I'll
get right to it.)

First off-- don't just Google for it and reference a single article with
out-of-context "cut and paste" elements from:
http://www.microsoft.com/technet/itsolutions/cits/mo/smf/smfsecad.mspx

You quote:
"advisable to make IPsec-based authentication a part of the authentication
process"

The actual text reads:
"As mentioned earlier, L2TP relies on other protocols for its security. L2TP
authentication is best for the exchange of packets between the LAC and the
LNS. Therefore, it is advisable to make IPSec-based authentication a part of
L2TP."  Other quotes are similar..

My original post was to content regarding actual authentication protocol
mechanisms like LM, NTLM, NTLMv2 and Kerberos.  The article you reference
does indeed use the phrase "IPSec Authentication," but as any who reads it
will see, the term is used to describe the higher level protocol deployment;
a higher
level protocol that has, as I said before, 3 authentication mechanisms
available to establish a connection.  Here's the article that should be
referenced:
http://www.microsoft.com/technet/prodtechnol/windowsserver2003/library/ServerHelp/be7540ff-2a1d-47b4-8e7f-501ec692ad11.mspx

The relevant text being:
<meat>
Overview of authentication methods:
For authentication, IPSec allows you to use the Kerberos V5 protocol,
certificate-based authentication, or preshared key authentication.
</meat>

Which is what I said the first time.

And not to be blunt, but your previous post describing the IPSec channel
setup of "system" and "client" is just wrong... the above link has many
other references that will help you understand how IPSec Policies and
component filters and actions work.  The "2 parts" are the default
negotiation, and the subsequent filter definitions.  Both of which still
require a PSK, Kerberos auth, or cert to be established.

The data is all right there if you want to check it out-- I don't see any
reason to argue about it, and it's all right there in the documentation...
If you want to discuss this off-list, (in a constructive way) I'm happy to
do so, but I think we're done on the list... (except for my last response to
the first message- then I'm hitting the sack ;)

t



----- Original Message -----
From: "Craig Wright" <cwright () bdosyd com au>
To: "Thor (Hammer of God)" <thor () hammerofgod com>; <pand0ra.usa () gmail com>;
<pen-test () securityfocus com>
Sent: Thursday, September 22, 2005 12:01 AM
Subject: RE: Passwords with Lan Manager (LM) under Windows


PPPS

To drop a quote from Technet (Microsoft Corporation)
"IPsec based Authentication and integrity" and
"Initial security proposals involve using IPsec-based authentication"
"advisable to make IPsec-based authentication a part of the
authentication process"
"IPsec-based authentication is recommended"

To quote the "rmt-pi" working party from the IETF
"provided using IPsec-based authentication at the network layer"

"I'd have to say that there is no such thing..." - Please inform MSFT -
they seem to think there is

Craig

-----Original Message-----
From: Thor (Hammer of God) [mailto:thor () hammerofgod com]
Sent: 22 September 2005 3:46
To: Craig Wright; pand0ra.usa () gmail com; pen-test () securityfocus com
Subject: Re: Passwords with Lan Manager (LM) under Windows

Well, that's an issue with the client, not NTLMv2.  NTLMv2 is tight.  LM
sucks- that's obvious (and it was IBM, not MS that gave us that one.)
And yes, you can use precomputed tables against NTLM hashes, but not
against NTLMv2... The NTLM hash is keyed off of the password, but NTLMv2
hashes up the password with the user's domain/user data when generating
the key...
You can't precompile that data into a rainbow, you know?

Regarding the "IPsec based auth" reference (here I go again), I'd have
to say that there is no such thing... IPSec negotiation in Windows can
be based on one of three mechanisms:  A pre-shared key, Kerberos, or a
cert-- it is not an authentication protocol in itself... (the cert being
the strongest IMO).

t


----- Original Message -----
From: "Craig Wright" <cwright () bdosyd com au>
To: "Thor (Hammer of God)" <thor () hammerofgod com>;
<pand0ra.usa () gmail com>; <pen-test () securityfocus com>
Sent: Wednesday, September 21, 2005 10:05 PM
Subject: RE: Passwords with Lan Manager (LM) under Windows


Further to the last post
There are a number of issues with NTLMv2 and legacy applications such as
Windows RAS that cause lower levels of authentication

I still say that Kerberos or IPsec based auth is the best policy in
windows. LanMan, NTLMv1 or V2 are vulnerable.

Precomputed tables may have been uncommon 12 months ago - but that was
then and this is now.

Cain & Abel will use sorted Rainbow Tables for Cryptanalysis attacks

Craig

-----Original Message-----
From: Thor (Hammer of God) [mailto:thor () hammerofgod com]
Sent: 22 September 2005 12:00
To: Craig Wright; pand0ra.usa () gmail com; pen-test () securityfocus com
Subject: Re: Passwords with Lan Manager (LM) under Windows


----- Original Message -----
From: "Craig Wright" <cwright () bdosyd com au>
To: <pand0ra.usa () gmail com>; <pen-test () securityfocus com>
Sent: Wednesday, September 21, 2005 12:32 PM
Subject: RE: Passwords with Lan Manager (LM) under Windows


Even NTLMv2  will break the hashing into chunks which are able to be
individually broken down.

I'm not sure what you mean... NTLMv2 uses a single 128bit key for the
hash, challenge and response...  Or are you referring to the NTLM2
session response key (56+56+16)? If so, that is not the same thing as
NTLMv2...
Can
you elaborate please ?

t









         


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