What Is A Ping And How Does It Work? - TechTarget

What is ping spoofing?

Ping spoofing, also known as IP spoofing, is a type of network attack in which threat actors falsify the source IP address in ICMP echo request packets to disguise the sender's identity and/or redirect responses to another device.

In a legitimate ping interaction, the source IP address in the ICMP echo request packet is that of the sender, and the destination device replies directly to the sender's address with an echo reply. In a spoofed ping, the attacker modifies the packet header to make it appear as though the request came from a different IP address. This way, the target's replies are misdirected to the spoofed (fake) IP address.

Effects of ping spoofing

Ping spoofing is often used as part of larger attack strategy, where the main goal is to overwhelm the victim's server by sending it an extremely large number of echo request packets within a short period of time. The resulting responses tie up the server's resources and can make the server inaccessible to legitimate users.

Historically, ping spoofing was used in amplification-based attacks, like ping of death. Ping of death is a type of distributed denial-of-service (DDoS) attack in which an attacker sends oversized ping packets to crash a targeted system.

How to detect ping spoofing

Ping spoofing can be difficult to detect because fraudulent echo request packets are designed to appear as if they come from a legitimate source.

To identify suspicious or spoofed ping traffic, one of the first things to look for is an unusually high number of ICMP echo requests that target the same host and are sent from the same IP address.

To investigate further, network administrators can analyze network logs and packet headers and look for anomalies such as malformed ICMP packets, inconsistent TTL values or improbable source IP locations. These signs, especially when seen in large volumes, may also indicate spoofing attempts.

How to defend against ping spoofing

In the past, one of the most common ways for admins to defend against ping spoofing was to use a firewall. Firewalls, along with access control lists on routers or switches, can filter incoming ICMP packets and apply rules that block traffic appearing to originate from forged or invalid source IP addresses.

Today, detecting ping spoofing is easier than it was in the past. Modern network monitoring tools and intrusion detection systems -- especially those enhanced with AI and machine learning capabilities -- can be configured to programmatically identify abnormal ICMP traffic patterns and alert administrators to potential spoofing activity. These advanced systems are also capable of recognizing subtle anomalies that probably would have gone unnoticed by traditional rule-based security tools.