👉 Overview
👀 What ?
EIGRP (Enhanced Interior Gateway Routing Protocol) is a Cisco proprietary advanced distance-vector routing protocol. This protocol is used on a computer network for automating routing decisions and configuration. An EIGRP attack is an attempt to disrupt or exploit the operation of a network that uses EIGRP.
🧐 Why ?
Understanding EIGRP attacks is important as these attacks can lead to significant network disruption, including denial of service (DoS), unauthorized network access, and data theft. Network engineers, cybersecurity professionals, and anyone involved in network design and operation would be particularly interested in this topic. EIGRP attacks exploit vulnerabilities in the EIGRP protocol to achieve their ends, making it crucial to understand these attacks to secure networks effectively.
⛏️ How ?
To prevent EIGRP attacks, one can implement a number of measures. These include: using encrypted communication where possible, configuring EIGRP authentication, limiting the number of EIGRP peers, and regularly updating and patching network devices. It's also important to monitor network traffic for unusual activity that could indicate an attack.
⏳ When ?
EIGRP was first introduced by Cisco in the mid-1990s. Attacking strategies have been developed since then as the protocol has become more widely used and its vulnerabilities have been discovered and exploited.
⚙️ Technical Explanations
An example of an EIGRP attack could be as follows:
- Discover the Network: Initially, the attacker would use a tool such as Nmap to scan the network and identify potential targets that are running EIGRP. This can be done with the following command:
nmap -p 88 [target IP range]
This command scans the specified IP range for machines that have port 88 (the standard EIGRP port) open.
- Spoof EIGRP 'Hello' Packets: Next, the attacker would use a packet crafting tool, such as Scapy in Python, to create and send spoofed EIGRP 'Hello' packets. The code might look something like this:
from scapy.all import *
# Create an EIGRP Hello packet
packet = IP(dst="target IP")/EIGRP(opcode="Hello", asn=1)
# Send the packet
send(packet)
This script sends a spoofed EIGRP 'Hello' packet to the target IP address. It uses the Autonomous System Number (ASN) of 1, which is common in many default configurations.
- Inject False Routes: Once the attacker has established themselves as a trusted EIGRP neighbor, they could begin injecting false routes into the network. This could be done by sending additional EIGRP packets with false routing information. For example:
# Create a false EIGRP route
packet = IP(dst="target IP")/EIGRP(opcode="Update", asn=1, routes=[EIGRPEntry(dst="false route IP")])
# Send the packet
send(packet)
This script sends an EIGRP 'Update' packet with a false route to the target IP.
- Monitor the Effects: Finally, the attacker could monitor the effects of their attack. This might involve watching network traffic with a tool such as Wireshark to see if traffic is being redirected as expected.
In this example, the attacker has caused network disruption and potentially gained access to sensitive information by exploiting the EIGRP protocol. However, it's important to note that such activities are illegal and unethical. This example is provided for educational purposes only, to help network administrators better understand and defend against such attacks.