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

certleader.com

Q1. John wants to try a new hacking tool on his Linux System. As the application comes from a site in his untrusted zone, John wants to ensure that the downloaded tool has not been Trojaned. Which of the following options would indicate the best course of action for John? 

A. Obtain the application via SSL 

B. Obtain the application from a CD-ROM disc 

C. Compare the files’ MD5 signature with the one published on the distribution media 

D. Compare the file’s virus signature with the one published on the distribution media 

Answer: C

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

Q2. WWW wanderers or spiders are programs that traverse many pages in the World Wide Web by recursively retrieving linked pages. Search engines like Google, frequently spider web pages for indexing. 

How will you stop web spiders from crawling certain directories on your website? 

A. Place robots.txt file in the root of your website with listing of directories that you don't want to be crawled 

B. Place authentication on root directories that will prevent crawling from these spiders 

C. Place "HTTP:NO CRAWL" on the html pages that you don't want the crawlers to index 

D. Enable SSL on the restricted directories which will block these spiders from crawling 

Answer: A

Explanation: WWW Robots (also called wanderers or spiders) are programs that traverse many pages in the World Wide Web by recursively retrieving linked pages. The method used to exclude robots from a server is to create a file on the server which specifies an access policy for robots. This file must be accessible via HTTP on the local URL "/robots.txt". http://www.robotstxt.org/orig.html#format 

Q3. You are concerned that someone running PortSentry could block your scans, and you decide to slow your scans so that no one detects them. Which of the following commands will help you achieve this? 

A. nmap -sS -PT -PI -O -T1 <ip address> 

B. nmap -sO -PT -O -C5 <ip address> 

C. nmap -sF -PT -PI -O <ip address> 

D. nmap -sF -P0 -O <ip address> 

Answer:

Explanation: -T[0-5]: Set timing template (higher is faster) 

Q4. _______ is one of the programs used to wardial. 

A. DialIT 

B. Netstumbler 

C. TooPac 

D. Kismet 

E. ToneLoc 

Answer: E

Explanation: ToneLoc is one of the programs used to wardial. While this is considered an "old school" technique, it is still effective at finding backdoors and out of band network entry points. 

Q5. Neil is closely monitoring his firewall rules and logs on a regular basis. Some of the users have complained to Neil that there are a few employees who are visiting offensive web site during work hours, without any consideration for others. Neil knows that he has an up-to-date content filtering system and such access should not be authorized. What type of technique might be used by these offenders to access the Internet without restriction? 

A. They are using UDP that is always authorized at the firewall 

B. They are using an older version of Internet Explorer that allow them to bypass the proxy server 

C. They have been able to compromise the firewall, modify the rules, and give themselves proper access 

D. They are using tunneling software that allows them to communicate with protocols in a way it was not intended 

Answer: D

Explanation: This can be accomplished by, for example, tunneling the http traffic over SSH if you have a SSH server answering to your connection, you enable dynamic forwarding in the ssh client and configure Internet Explorer to use a SOCKS Proxy for network traffic. 

Q6. RC4 is known to be a good stream generator. RC4 is used within the WEP standard on wireless LAN. WEP is known to be insecure even if we are using a stream cipher that is known to be secured. 

What is the most likely cause behind this? 

A. There are some flaws in the implementation. 

B. There is no key management. 

C. The IV range is too small. 

D. All of the above. 

E. None of the above. 

Answer: D

Explanation: Because RC4 is a stream cipher, the same traffic key must never be used twice. The purpose of an IV, which is transmitted as plain text, is to prevent any repetition, but a 24-bit IV is not long enough to ensure this on a busy network. The way the IV was used also opened WEP to a related key attack. For a 24-bit IV, there is a 50% probability the same IV will repeat after 5000 packets. Many WEP systems require a key in hexadecimal format. Some users choose keys that spell words in the limited 0-9, A-F hex character set, for example C0DE C0DE C0DE C0DE. Such keys are often easily guessed. 

Q7. What type of Virus is shown here? 

A. Cavity Virus 

B. Macro Virus 

C. Boot Sector Virus 

D. Metamorphic Virus 

E. Sparse Infector Virus 

Answer: E

Q8. What do you conclude from the nmap results below? 

Staring nmap V. 3.10ALPHA0 (www.insecure.org/map/) 

(The 1592 ports scanned but not shown below are in state: closed) 

PortStateService 21/tcpopenftp 25/tcpopensmtp 80/tcpopenhttp 443/tcpopenhttps 

Remote operating system guess: Too many signatures match the reliability guess the OS. Nmap run completed – 1 IP address (1 host up) scanned in 91.66 seconds 

A. The system is a Windows Domain Controller. 

B. The system is not firewalled. 

C. The system is not running Linux or Solaris. 

D. The system is not properly patched. 

Answer:

Explanation: There is no reports of any ports being filtered. 

Q9. In this attack, a victim receives an e-mail claiming from PayPal stating that their account has been disabled and confirmation is required before activation. The attackers then scam to collect not one but two credit card numbers, ATM PIN number and other personal details. 

Ignorant users usually fall prey to this scam. Which of the following statement is incorrect related to this attack? 

A. Do not reply to email messages or popup ads asking for personal or financial information 

B. Do not trust telephone numbers in e-mails or popup ads 

C. Review credit card and bank account statements regularly 

D. Antivirus, anti-spyware, and firewall software can very easily detect these type of attacks 

E. Do not send credit card numbers, and personal or financial information via e-mail 

Answer: A

Q10. Take a look at the following attack on a Web Server using obstructed URL: 

http://www.example.com/script.ext?template%2e%2e%2e%2e%2e%2f%2e%2f%65%74%63%2f %70%61%73%73%77%64 

The request is made up of: 

-%2e%2e%2f%2e%2e%2f%2e%2f% = ../../../ 

-%65%74%63 = etc 

-%2f = / 

-%70%61%73%73%77%64 = passwd 

How would you protect information systems from these attacks? 

A. Configure Web Server to deny requests involving Unicode characters. 

B. Create rules in IDS to alert on strange Unicode requests. 

C. Use SSL authentication on Web Servers. 

D. Enable Active Scripts Detection at the firewall and routers. 

Answer: B

Explanation: This is a typical Unicode attack. By configuring your IDS to trigger on strange Unicode requests you can protect your web-server from this type of attacks.