Icmp Vulnerability; Illegal Commands (Netbios And Smtp); Figure 33 Smurf Attack; Table 27 Icmp Commands That Trigger Alerts - ZyXEL Communications ZyWall P1 User Manual

ZyWALL P1 User's Guide

Figure 33 Smurf Attack

6.4.2.1 ICMP Vulnerability

ICMP is an error-reporting protocol that works in concert with IP. The following ICMP types
trigger an alert:

Table 27 ICMP Commands That Trigger Alerts

5 REDIRECT
13 TIMESTAMP_REQUEST
14 TIMESTAMP_REPLY
17 ADDRESS_MASK_REQUEST
18 ADDRESS_MASK_REPLY

6.4.2.2 Illegal Commands (NetBIOS and SMTP)

The only legal NetBIOS commands are the following - all others are illegal.

Table 28 Legal NetBIOS Commands

MESSAGE:
REQUEST:
POSITIVE:
NEGATIVE:
RETARGET:
KEEPALIVE:
96 Chapter 6 Firewalls