From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Clark Subject: DNS rebinding Date: Tue, 07 Aug 2007 12:11:11 -0400 Message-ID: <46B8999F.3060202@seclark.us> Reply-To: Stephen.Clark@seclark.us Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit To: netfilter-devel@lists.netfilter.org Return-path: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: netfilter-devel-bounces@lists.netfilter.org Errors-To: netfilter-devel-bounces@lists.netfilter.org List-Id: netfilter-devel.vger.kernel.org Hello List, There is an article about DNS rebinding at the following site: http://crypto.stanford.edu/dns/ "Circumvention-Resistant Firewalls. Firewalls can prevent their own circumvention by forbidding external host names from resolving to internal IP addresses, preventing the attacker from naming the target server, either by filtering packets [6] or by modifying their DNS resolver." Can netfilter be setup to keep dns responses from pointing to internal addresses by filtering the packets? If so how would one go about setting that up. Thanks, Steve -- "They that give up essential liberty to obtain temporary safety, deserve neither liberty nor safety." (Ben Franklin) "The course of history shows that as a government grows, liberty decreases." (Thomas Jefferson)