Re: Pen-testing remote VPN services over IP

[Michael Thumann <mlthumann () ids-guide de>]

Hi,

we just published a tool called ikeprobe that checks for devices that are 
vulnerable to the PSK Attack we've described in our paper 'PSK Cracking 
using IKE Aggressive Mode'.

You can find the paper at www.ernw.de/download/pskattack.pdf and the tool 
ikeprobe at www.ernw.de/download/ikeprobe.zip.

Using ikeprobe together with Cain & Abel (www.oxid.it) you can check for 
the vulnerability and capture the PSK hash with Cain & Abel in one step. 
Cain & Abel can crack both, MD5 and SHA1 based hashes.

Hope that helps.
Michael

At 20:21 06.11.2003, Chris McNab wrote:
> Hi,
>
> As part of some research I am undertaking recently, I'd like to know if any
> of you have any decent information relating to the following areas of
> _remote_ assessment of VPN services over IP.
>
> The topics I have covered and documented fully so far include:
>
> - IPsec enumeration, scanning for UDP/500 and using Roy Hills' tools
> (ike-scan) to identify the gateway
> - Various overflows relating to ISAKMP / IKE packets being sent to UDP/500,
> as in MITRE CVE
> - Offline aggressive mode IKE pre-shared key cracking, by sniffing VPN
> traffic and using IKECrack
> - Check Point aggressive mode IKE username enumeration (using Roy Hills'
> fw1-ike-userguess over UDP/500)
> - Check Point Telnet authentication service (TCP/259) user enumeration
> - Check Point information leak attacks that reveal network interface
> addresses, over both TCP/256 and TCP/264
> - Check Point RDP encapsulation filter bypass techniques, using UDP/259
> - Offline Microsoft PPTP (TCP/1723) MS-CHAP challenge-response cracking
>
> Two areas in which I've identified a need for tools are:
>
> - Check Point brute force password grinding tool for FWZ or IKE, to
> compromise SecuRemote username/password combinations
> - PPTP brute force tool, to compromise those user/password combinations also
>
> Does anyone know of such offensive brute force tools, or techniques I have
> missed (against ISAKMP and Check Point)? if so, any input would be greatly
> appreciated.
>
> Regards,
>
> Chris
>
>
> Chris McNab
> Technical Director
>
> Matta
> 18 Noel Street
> London W1F 8GN
>
> http://www.trustmatta.com
>
>
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Michael Thumann        mlthumann@ids-guide       www.ids-guide.de
Public Key available at http://www.ids-guide.de/MichaelThumann.asc
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