Using SmartDefense
Max Ping Size
PING (ICMP echo request) is a program that uses ICMP protocol to check whether
a remote machine is up. The client sends a request, and the server responds with a
reply echoing the client's data.
An attacker can echo the client with a large amount of data, causing a buffer
overflow. You can protect against such attacks by limiting the allowed size for
ICMP echo requests.
Table 40: Max Ping Size Fields
In this field… Do this…
Action
Max
Specify what action to take when an ICMP echo response exceeds the
Ping Size
threshold, by selecting one of the following:
•
Block.
Block the request. This is the default.
•
None.
No action.
Track
Specify whether to log ICMP echo responses that exceed the
Max Ping Size
threshold, by selecting one of the following:
•
Log.
Log the responses. This is the default.
•
None.
Do not log the responses.
Chapter 9: Setting Your Security Policy
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