Suspicious Packet Attributes Overview

Attackers can craft packets to perform reconnaissance or launch denial-of-service (DoS) attacks. Sometimes it is unclear what the intent of a crafted packet is, but the very fact that it is crafted suggests that it is being put to some kind of insidious use.

The following topics describe screen options that block suspicious packets that might contain hidden threats:

• Understanding ICMP Fragment Protection

• Understanding Large ICMP Packet Protection

• Understanding Bad IP Option Protection

• Understanding Unknown Protocol Protection

• Understanding IP Packet Fragment Protection

• Understanding SYN Fragment Protection