1. CS4622: Computer Networking
Group 3: Network Security
Ayham Hmemes
Hamilton Bradford
Janelle Bright
Jonathan Reagan
Peter Wang

2. ARP POISONING

3. A BRIEF OVERVIEW :
ARP: maps the logical address to the physical address (given logical, find physical)
Keep in mind that the Tx doesn’t know the physical address of the Rx – and the IP address alone IS NOT enough info to tell the Tx where the RX is located – this is the problem ARP solves
The Tx broadcast out an ARP query packet to all stations on the network – the packet contains the Tx’s physical/IP addresses and the IP address it’s seeking to find a physical address for.
All stations on the network receives the query packet however, only the station with that IP responds
The responding Rx sends back it’s physical address (in a unicast form) to the Tx
Now the Tx can unicast the actual data to the Rx

4. Computer 1 → computer 2
Computer 1 → computer 3
Arp table for computer 1 will have :
Computer 1 will be able to communicate with computer 2 and 3, because now it has both ip and mac address for each one of them.
IP Addresses
Mac Addresses
Computer 2 IP address
Computer 2 MAC address
Computer 3 IP address
Computer 3 MAC address

5. ARP POISONING: IP Address MAC address Router’s IP address
We will send fake ARP requests to the target, linking our MAC address with the IP address of the Gateway (Router)
So the victim’s Arp table will look like :
So now all the traffic that the victim sends to Wi-Fi Router, will be directed to us , but not to the Gateway
IP Address
MAC address
Router’s IP address
Our (hacker) MAC address

6. Redirect the received data after spying or modifying it
Let’s see this visually:
data
Redirect the received data after spying or modifying it
Fake ARP requests

7. TIPS TO PREVENT ARP SPOOFING
If your network has been compromised by ARP spoofing, there are some methods you can try to prevent further damage or privacy breach.
Use Anti-ARP Tools
If you have any idea of what type of ARP spoofing tool the attacker is using, find a tool that can counter it. Using static ARP is one of the many methods to prevent ARP spoofing attack. However, static ARP can only prevent simple ARP attacks, and cannot be relied upon as a failsafe ARP spoofing defense tool.
Use ARP-Spoofing Proof Switches
Most modern switches come with the built-in ARP spoofing protection feature. You can use these switches to protect your network or computer from ARP spoofing attacks and ensure the protection of your privacy.
Use Virtual Private Networks
One of the best ways to protect your computer from ARP spoofing attack is by using a VPN.  A VPN will allow you to do online activities through an encrypted tunnel. Not only is the mode of transmission encrypted but also the data that goes through it.
So, even if your network is compromised by ARP spoofing, your privacy, data or conversation will remain secure because the attacker won’t be able to decrypt the 256-bit encrypted data.

8. NON-MALICIOUS USE Proxy ARP1
Proxy ARP allows for multiple physical networks to act as though they were on the same subnet.
Network Debugging
Exactly how an attacker would use ARP poisoning, it can be used to analyze packets being sent across a network.
Firewalls
Firewalls can filter packets before they reach the network.
1https://

9. DNS SPOOFING

10. A BRIEF OVERVIEW DNS resolves symbolic domain names to IP addresses
Security was not considered during design of DNS

11. DNS SPOOFING1
Because DNS responses are predictable, the only thing an attacker needs to guess is the Transaction ID (generally 16 bits)
Kaminsky exploit builds on this and compromises a domain by attacking an authoritative server
Once successful, the attack remains until the response TTL expires
1https://

12. MAN IN THE MIDDLE
Targets local networks instead of a vulnerable DNS Resolver
Implements ARP Spoofing to intercept DNS requests to/from target and change them

13. TIPS TO PREVENT DNS SPOOFING
DNS Encryption
DNSSEC
Port Randomization
Increasing expiry time for legitimate DNS requests in the cache

14. SQL INJECTION

15. A BRIEF OVERVIEW SQL Programming language used primarily for databases
Created in 1986
Most in-demand programming language for 2017
Companies such as Google, Facebook, and Twitter use SQL
Notorious for its major security flaws

16. A BRIEF OVERVIEW SQL Injection
One of the most common hacking techniques
Injects malicious code in order to manipulate databases
An SQL injection can both insert or delete data in the database

17. WHAT IS SQL INJECTION

18. TIPS TO PREVENT SQL INJECTION
Prevention is quite simple
mySQL_real_escape_string(“...”)
Prepared Statements
Various scripts and guides exist to check for SQL injection vunerabilites

19. SOURCES