Cisco IDS-4230-FE - Intrusion Detection Sys Fast Ethernet Sensor Datový list stáhnout pdf (Strana 7)

642-531

3) Unicode representation.

Cisco Courseware 3-27

QUESTION 16

Why would an attacker saturate the network with "noise" while simultaneously launching an attack?

A. causes the IDS to fire multiple false negative alarms

B. an attack may go undetected

C. it will have no effect on the sensor's ability to detect attacks

D. to initiate asymmetric attack techniques

Answer: B

Explanation:

By flooding the network with noise traffic and causing the IDS to capture unnecessary packets, the attacker can

launch an attack that can go undetected. If the attack is detected, the IDS resources may be exhausted causing a

delayed response and thus is unable to respond in a timely manner. In the figure, the attacker is sending large

amounts of traffic as signified by the larger pipe. Meanwhile, the actural attack is being sent to the target host,

as represented by the thin pipe that reaches the target host.

Cisco Courseware 3-24

QUESTION 17

An attacker has launched an attack against a web server by requesting a web page using the Unicode

representation for the slash character in the URL.

What IDS evasive technique is the attacker using?

A. Encryption

B. Fragmentation

C. Flooding

D. Obfuscation

E. Saturation

Answer: D

Explanation: Intrusion detection systems typically implement obfuscation defense - ensuring that suspect

packets cannot easily be disguised with UTF and/or hex encoding and bypass the Intrusion Detection systems.

Reference: Cisco Intrusion Detection System - Cisco Security Advisory: Cisco Secure Intrusion Detection

System Signature Obfuscation Vulnerability

QUESTION 18

Which of the following represents valid responses to an active attack by PIX-IDS and IOS-IDS

platforms? (Choose two.)

A. initiate shunning/blocking

B. IP logging

C. drop the offending packets

1 2 3 4 5 6 7 8 9 10 11 12 ... 122 123

Žádné komentáře

Cisco IDS-4230-FE - Intrusion Detection Sys Fast Ethernet Sensor Datový list Strana 7