312-50 Exam - Ethical Hacking and Countermeasures (CEHv6)

certleader.com

Q1. John wishes to install a new application onto his Windows 2000 server. 

He wants to ensure that any application he uses has not been Trojaned. 

What can he do to help ensure this? 

A. Compare the file's MD5 signature with the one published on the distribution media 

B. Obtain the application via SSL 

C. Compare the file's virus signature with the one published on the distribution media 

D. Obtain the application from a CD-ROM disc 

Answer: A

Explanation: MD5 was developed by Professor Ronald L. Rivest of MIT. What it does, to quote the executive summary of rfc1321, is: 

[The MD5 algorithm] takes as input a message of arbitrary length and produces as output a 128-bit "fingerprint" or "message digest" of the input. It is conjectured that it is computationally infeasible to produce two messages having the same message digest, or to produce any message having a given prespecified target message digest. The MD5 algorithm is intended for digital signature applications, where a large file must be "compressed" in a secure manner before being encrypted with a private (secret) key under a public-key cryptosystem such as RSA. 

In essence, MD5 is a way to verify data integrity, and is much more reliable than checksum and many other commonly used methods. 

Q2. SYN Flood is a DOS attack in which an attacker deliberately violates the three-way handshake and opens a large number of half-open TCP connections. 

The signature for SYN Flood attack is: 

A. The source and destination address having the same value. 

B. The source and destination port numbers having the same value. 

C. A large number of SYN packets appearing on a network without the corresponding reply packets. 

D. A large number of SYN packets appearing on a network with the corresponding reply packets. 

Answer: C

Explanation: A SYN attack occurs when an attacker exploits the use of the buffer space during a Transmission Control Protocol (TCP) session initialization handshake. The attacker floods the target system's small "in-process" queue with connection requests, but it does not respond when a target system replies to those requests. This causes the target system to time out while waiting for the proper response, which makes the system crash or become unusable. 

Q3. An attacker has been successfully modifying the purchase price of items purchased at a web site. The security administrators verify the web server and Oracle database have not been compromised directly. They have also verified the IDS logs and found no attacks that could have caused this. What is the mostly likely way the attacker has been able to modify the price? 

A. By using SQL injection 

B. By using cross site scripting 

C. By changing hidden form values in a local copy of the web page 

D. There is no way the attacker could do this without directly compromising either the web server or the database 

Answer: C

Explanation: Changing hidden form values is possible when a web site is poorly built and is trusting the visitors computer to submit vital data, like the price of a product, to the database. 

Q4. What is the key advantage of Session Hijacking? 

A. It can be easily done and does not require sophisticated skills. 

B. You can take advantage of an authenticated connection. 

C. You can successfully predict the sequence number generation. 

D. You cannot be traced in case the hijack is detected. 

Answer: B

Explanation: As an attacker you don’t have to steal an account and password in order to take advantage of an authenticated connection. 

Q5. What is War Dialing? 

A. War dialing involves the use of a program in conjunction with a modem to penetrate the modem/PBX-based systems 

B. War dialing is a vulnerability scanning technique that penetrates Firewalls 

C. It is a social engineering technique that uses Phone calls to trick victims 

D. Involves IDS Scanning Fragments to bypass Internet filters and stateful Firewalls 

Answer: A

Q6. You are attempting to map out the firewall policy for an organization. You discover your target system is one hop beyond the firewall. Using hping2, you send SYN packets with the exact TTL of the target system starting at port 1 and going up to port 1024. What is this process known as? 

A. Footprinting 

B. Firewalking 

C. Enumeration 

D. Idle scanning 

Answer: B

Explanation: Firewalking uses a traceroute-like IP packet analysis to determine whether or not a particular packet can pass from the attacker’s host to a destination host through a packet-filtering device. This technique can be used to map ‘open’ or ‘pass through’ ports on a gateway. More over, it can determine whether packets with various control information can pass through a given gateway. 

Q7. You receive an e-mail with the following text message. 

"Microsoft and HP today warned all customers that a new, highly dangerous virus has been discovered which will erase all your files at midnight. If there's a file called hidserv.exe on your computer, you have been infected and your computer is now running a hidden server that allows hackers to access your computer. Delete the file immediately. Please also pass this message to all your friends and colleagues as soon as possible." 

You launch your antivirus software and scan the suspicious looking file hidserv.exe located in c:\windows directory and the AV comes out clean meaning the file is not infected. You view the file signature and confirm that it is a legitimate Windows system file "Human Interface Device Service". 

What category of virus is this? 

A. Virus hoax 

B. Spooky Virus 

C. Stealth Virus 

D. Polymorphic Virus 

Answer: A

Q8. Darren is the network administrator for Greyson & Associates, a large law firm in Houston. Darren is responsible for all network functions as well as any digital forensics work that is needed. Darren is examining the firewall logs one morning and notices some unusual activity. He traces the activity target to one of the firm's internal file servers and finds that many documents on that server were destroyed. After performing some calculations, Darren finds the damage to be around $75,000 worth of lost data. Darren decides that this incident should be handled and resolved within the same day of its discovery. 

What incident level would this situation be classified as? 

A. This situation would be classified as a mid-level incident 

B. Since there was over $50,000 worth of loss, this would be considered a high-level incident 

C. Because Darren has determined that this issue needs to be addressed in the same day it was discovered, this would be considered a low-level incident 

D. This specific incident would be labeled as an immediate-level incident 

Answer: D

Q9. Assuring two systems that are using IPSec to protect traffic over the internet, what type of general attack could compromise the data? 

A. Spoof Attack 

B. Smurf Attack 

C. Man in the Middle Attack 

D. Trojan Horse Attack 

E. Back Orifice Attack 

Answer: DE

Explanation: To compromise the data, the attack would need to be executed before the encryption takes place at either end of the tunnel. Trojan Horse and Back Orifice attacks both allow for potential data manipulation on host computers. In both cases, the data would be compromised either before encryption or after decryption, so IPsec is not preventing the attack. 

Q10. What is SYSKEY # of bits used for encryption? 

A. 40 

B. 64 

C. 128 

D. 256 

Answer: C

Explanation: System Key hotfix is an optional feature which allows stronger encryption of SAM. Strong encryption protects private account information by encrypting the password data using a 128-bit cryptographically random key, known as a password encryption key.