Network Poisoning
Network Poisoning is a cyber attack technique where attackers inject false information into a network to manipulate how traffic is routed. One of the most common forms is ARP Spoofing, where the attacker associates their MAC address with the IP address of another device, like the default gateway.
What is ARP?
ARP (Address Resolution Protocol) is used to map IP addresses to MAC addresses in a local network. When a device wants to send data to another IP on the network, it sends an ARP request to find the corresponding MAC address.
What is Network Poisoning?
In ARP poisoning, the attacker sends forged ARP replies to devices on the network, tricking them into associating the attacker’s MAC address with the IP of another machine, such as the router. This allows the attacker to intercept, modify, or block data between devices — effectively performing a Man-in-the-Middle (MITM) attack.
Techniques Used
- ARP Spoofing: Forging ARP replies to mislead devices.
- DHCP Spoofing: Acting as a rogue DHCP server to assign malicious configurations.
- ICMP Redirects: Sending false routing information.
Risks of Network Poisoning
- Data interception (sniffing login info, credentials, etc).
- Session hijacking and credential theft.
- Denial of Service (DoS) if attacker drops packets.
- Malware injection in transit (e.g., JavaScript injection).
Prevention Techniques
- Use Static ARP Entries: For critical systems.
- Enable Port Security: On switches to prevent MAC spoofing.
- Use HTTPS: Encrypt data to prevent sniffing.
- Monitor Traffic: Detect duplicate IPs or MACs.
- Use Tools: Such as arpwatch, XArp, or IDS/IPS systems.
Conclusion
Network poisoning is a powerful attack method that can compromise the confidentiality and integrity of network communications. Understanding and defending against such attacks is essential for penetration testers and defenders alike.