Question 1: Snort Rules Case Study - Essay Prowess

Question 1: Snort Rules Case Study

  

Scenario A small company has a network set up behind a NAT router. The router is connected to the Internet via a single ISP provided dynamic IP address. The ISP provided access address may change over short periods of time. The internal network is RFC 1918 Category 2 compliant, and uses the private address space 192.168.3.0/24. The gateway router is configured to use DHCP allocated IP addresses to internal hosts as they connect. However, a record is kept within the router of what IP addresses have previously been allocated to specific MAC addresses. Whenever those MAC addressed hosts disconnect from and later reconnect to the network they are reallocated the same IP address. It is only if the router has a power off episode, or is manually reset, that allocation of different IP addresses may occur (and even then, the same addresses may be allocated as before). The company operates an approved internal web server at 192.168.3.21:80, to facilitate in-house development of web pages and web sites that will later be deployed to an external server for public access. It is a company policy that only one approved internal web server is to be in operation on the network. You are the company IT Manager. It has come to your notice that a company employee has set up a rogue web server on the internal network, using a personal laptop. The employee is using that web site to provide undesirable material to a small clique of employees, to whom the web server address has been provided secretly. The company CEO has requested you to: Considerations Technical Approach to the Solution To carry out the CEO’s request you have decided to: A) Use Wireshark to capture packet data on the internal network. B) Use snort to monitor for any internal network HTTP traffic destined for any internal host on any port address other than the authorised company internal web server and produce an alert message. The snort monitoring will identify when breaches have occurred. The Wireshark pcap file containing the captured packets can be time correlated with the logged snort alerts to obtain MAC addresses for source and target. Your Task You are to write a .conf file containing the snort rule(s) that will accomplish the technical approach to a solution. Hint