A ping of death is a type of attack on a computer system that involves sending a malformed or otherwise malicious ping to a computer.
A correctly-formed ping packet is typically 56 bytes in size, or 64 bytes when the ICMP header is considered, and 84 including Internet Protocol version 4 header. However, any IPv4 packet (including pings) may be as large as 65,535 bytes. Some computer systems were never designed to properly handle a ping packet larger than the maximum packet size because it violates the Internet Protocol documented in RFC 791. Like other large but well-formed packets, a ping of death is fragmented into groups of 8 octets before transmission. However, when the target computer reassembles the malformed packet, a buffer overflow can occur, causing a system crash and potentially allowing the injection of malicious code.
In early implementations of TCP/IP, this bug is easy to exploit and can affect a wide variety of systems including Unix, Linux, Mac, Windows, and peripheral devices. As systems began filtering out pings of death through firewalls and other detection methods, a different kind of ping attack known as ping flooding later appeared, which floods the victim with so many ping requests that normal traffic fails to reach the system (a basic denial-of-service attack).
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