CAPEC-496: ICMP Fragmentation

MITRE CAPEC attack pattern

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.

Where this sits in the chain

A finding maps to a weakness (CWE), a weakness is exploited by an attack pattern (CAPEC), and an attack pattern shows up in ATT&CK as observed adversary behaviour. This page is the middle hop.

Weaknesses exploited: CWE-404, CWE-770

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.

Source

• MITRE CAPEC CAPEC-496