Home page logo

fulldisclosure logo Full Disclosure mailing list archives

RE: [Tool] HardTCP "Hardening TCP/IP" + SOURCE
From: DWreck <dwr3ckmailbox-fulldisclosure () yahoo com>
Date: Mon, 19 Jul 2004 07:45:20 -0700 (PDT)

Need to be careful when hardening the stack:

DefVal(8).Text = GetDWORDValue("HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Tcpip\Parameters", 
If DefVal(8).Text = "Error" Then DefVal(8).Text = "NP"
Disabling PMTU discovery sets the default MTU to 576 for all foreign networks.  In a properly segmented environment 
this setting can cause 3X the amount of packets sent between VLANs.

DefVal(11).Text = GetDWORDValue("HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Tcpip\Parameters", 
If DefVal(11).Text = "Error" Then DefVal(11).Text = "NP"

Note:  Make sure IDRP is not in use in the clientÂ’s perimeter network.

Also, since the interface name changes whenever NICs are added/removed, keeping this edit in can be rough in large 

As for the rest, I've had 0 issues with the settings when implementing across 2000+ servers.



CONFIDENTIALITY NOTICE: This e-mail and any attachments thereto may contain information which is privileged and 
confidential, and is intended for the sole use of the recipient(s) named above. Any use of the information contained 
herein (including, but not limited to, total or partial reproduction, communication or distribution in any form) by 
persons other than the designated recipient(s) is strictly prohibited. If you have received this e-mail in error, 
please notify the sender either by telephone or by e-mail and delete the material from any computer. Thank you for your 

  By Date           By Thread  

Current thread:
  • RE: [Tool] HardTCP "Hardening TCP/IP" + SOURCE DWreck (Jul 19)
[ Nmap | Sec Tools | Mailing Lists | Site News | About/Contact | Advertising | Privacy ]