Description

An attacker may execute a ICMP Fragmentation attack against a target with the intention of consuming resources or causing a crash. The attacker crafts a large number of identical fragmented IP packets containing a portion of a fragmented ICMP message. The attacker these sends these messages to a target host which causes the host to become non-responsive. Another vector may be sending a fragmented ICMP message to a target host with incorrect sizes in the header which causes the host to hang.

Prerequisites

This type of an attack requires the target system to be running a vulnerable implementation of IP, and the attacker needs to ability to send arbitrary sized ICMP packets to the target.

Mitigations

This attack may be mitigated through egress filtering based on ICMP payload so a network is a "good neighbor" to other networks. Bad IP implementations become patched, so using the proper version of a browser or OS is recommended.