Cybersecurity Concepts and Techniques, Exams of Computer Security

Download Cybersecurity Concepts and Techniques and more Exams Computer Security in PDF only on Docsity! COMPUTER SECURITY MIDTERM (ALL SETS) QUESTIONS AND ANSWERS 2024 LATEST UPDATED AND GRADED A+ What were the motivations of traditional external hackers? - Solution Ego, the trill of the break-in, and the validation of their skills Did traditional external hackers engage in theft? - Solution They often did What is an exploit? - Solution The specific attack method that the attacker uses to break into the computer What does "owning" a computer mean? - Solution Being able to do anything the attacker wishes on the computer. What is IP address spoofing? - Solution Sending packets with false IP source addresses. Why is IP address spoofing done? - Solution So that the attacker cannot determine the identity of the attacker. When can an attacker not use IP address spoofing? - Solution when they are trying to read replies of probe packets. How can social engineering be used to get access to a sensitive file? - Solution Simply by asking someone to send the file or to give access to the file What is piggybacking? - Solution Following someone through the door to a secure area without authenticating oneself. What is shoulder surfing? - Solution Watching someone type his or her password in order to learn the password. What is pretexting? - Solution an attacker calls claiming to be a certain person in order to ask for private information about that person. What is a DoS attack? - Solution attack that attempts to make a server or network unavailable to serve legitimate users by flooding it with attack packets Describe a DDoS attack. - Solution an attacker controls many computers with bots. The attacker (or "botmaster") sends the bots a command to attack. All the bots then send the victim a flood of attack packets Why do many botnets have multiple owners over time? - Solution Typically, a botmaster will use the botnet for his or her purpose, then sell the botnet to someone else. What are the two primary characteristics of skilled hackers? - Solution Strong technical skills and dogged persistence Why are script kiddies dangerous? - Solution because of their sheer numbers and because their many attacks make it difficult to recognize the few attacks that are highly sophisticated Why are malware and exploit toolkits expanding the danger of script kiddies? - Solution They are making it much easier for script kiddies to act. What is a governance framework? - Solution Something that specifies how to do planning, implementation, and oversight. What does COSO focus on - Solution It focuses on corporate level governance What does COBIT focus on - Solution It focuses on IT governance What are the four objectives of COSO? - Solution Strategic, Operations, Reporting, and Compliance List the four COBIT domains. - Solution Planning & organization; acquisition & implementation; delivery & support; and monitoring How many high-level control objectives does COBIT have? - Solution 34 How many detailed control objectives does COBIT have? - Solution More than 300 What are the three key lengths offered by AES? - Solution 128 bit, 192 bit, and 256 bit. Which strong symmetric key encryption cipher can be used with small mobile devices? - Solution AES can be used with small mobile devices. Which symmetric key encryption cipher probably will dominate in the near future? - Solution AES What is security through obscurity, and why is it bad? - Solution It relies on attackers not to obtain learnable information and it is bad because it could result in catastrophic loss of security if known. What is an impostor? - Solution someone who pretends to be someone else What is authentication? - Solution Proving your identity to communicate to a partner What is mutual authentication? - Solution When both parties authenticate themselves to the other Why is a secure keying phase necessary? - Solution because if the key is not protected, it can be stolen and this will defeat the purpose of encrypting the data. What three protections do cryptographic systems provide on a message- by-message basis? - Solution An electronic signature, message integrity, and message encryption. What is an electronic signature? - Solution a field in a message that authenticates the message. What two protections do electronic signatures usually provide? - Solution message-by-message authentication and message integrity In SSL/TLS, what is a cipher suite? - Solution a specific set of options for a particular cryptographic system standard. What are credentials? - Solution They are proofs of identity Is encryption reversible? - Solution It is reversible Is hashing reversible? - Solution It is irreversible. Is hashing repeatable? - Solution it is repeatable When a hashing algorithm is applied, does the hash have a fixed length or a variable length? - Solution It will have a fixed length What is the hash size of MD5? - Solution 128 bits What is the hash size of SHA-1? - Solution 160 bits What is the hash size of SHA-256? - Solution 256 bits Which hashing algorithm is currently recommended for use by NIST? - Solution SHA-2 Is MS-CHAP used for initial authentication or message-by-message authentication? - Solution used for initial authentication In a classroom with 30 students and a teacher, how many public keys will there be? - Solution 30 What is the main drawback to public key encryption? - Solution it is slow and expensive to use. What is the most popular public key encryption cipher? - Solution RSA What is the other commonly used public key encryption cipher? - Solution ECC is increasing in use How long are strong RSA keys? - Solution 1,024 bits What is the purpose of Diffie-Hellman key exchange? - Solution Keying Can an attacker who captures the exchanged keying information compute the symmetric session key? - Solution No What is a man-in-the-middle attack? - Solution A form of attack in which an attacker intercepts messages being sent between two parties and forwards them on What is a replay attack? - Solution It's where an adversary intercepts an encrypted message and transmits it again later. In public key authentication, what must the sender know that an impostor should not be able to learn? - Solution The true party's private key For what type of authentication is a digital signature used—initial authentication or message-bymessage authentication? - Solution Digital signatures How does the supplicant create a message digest? - Solution by hashing the plaintext message. How does the supplicant create a digital signature? - Solution by encrypting the message digest with its own private key In public key encryption, what is "signing?" - Solution the act of encrypting the message digest with its own private key What combined message does the supplicant send? - Solution It is the digital signature plus the plaintext How is the combined message encrypted for confidentiality? - Solution The sender will use symmetric key encryption. Besides authentication, what security benefit does a digital signature provide? - Solution Message integrity From what kind of organization can a verifier receive digital certificates? - Solution The certificate authority (CA) Are most CAs regulated? - Solution CAs in many countries are not regulated What are the two most critical fields in the digital certificate? - Solution The name of the true party and the true party's public key What is a Smurf flood? - Solution a variation of a reflected attack that takes advantage of an incorrectly configured network device (router) to flood a victim What is black holing? - Solution when a firm drops all IP packets from an attacker. How can the effects of SYN floods be mitigated? - Solution by validating the TCP handshake, rate limiting, or even black holing Can ARP poisoning be used outside the LAN? - Solution Typically not What is ARP spoofing? - Solution uses false ARP replies to map any IP address to any MAC address How could an attacker use ARP spoofing to manipulate host ARP tables? - Solution they do not require authentication or verification Do switches record IP addresses? - Solution No, they only look at MAC addresses What is the main access control threat to wireless LANs? - Solution An intruder can connect by radio to an unprotected wireless access point. Is eavesdropping usually a concern for wired LANs, wireless LANs, or both? - Solution It is a concern in both Why is 802.1X called Port-Based Access Control? - Solution because security is implemented on specific ports of an Ethernet workgroup switch Where is the heavy authentication work done? - Solution on a central authentication server How does an EAP session start? - Solution When a switch senses a connection, it sends an EAP Start message to the RADIUS server. What types of messages carry requests for authentication information and responses to these requests? - Solution EAP request and response messages. When a new authentication method is added, what device software must be changed to use the new method? - Solution the central authentication server and supplicant What standard do most central authentication servers follow? - Solution the RADIUS standard How are EAP and RADIUS related in terms of functionality? - Solution RADIUS is an AAA server that uses EAP for authentication What authentication method does RADIUS use? - Solution EAP What is the most common attack against wireless networks? - Solution unauthorized access, or connecting to a network without permission. Which IEEE standard governs WLAN transmission? - Solution IEEE 802.11 Which device acts as a relay between wired and wireless networks? - Solution An access point What is the typical range of a WLAN? - Solution 30 to 100 meters extending in all directions from the AP Who would set up a rogue access point? - Solution internal employees for convenience Are you liable if someone else uses your wireless network to commit a crime? - Solution not liable for crimes committed by criminals using your wireless network if you attempted to secure it What man-in-the-middle attack is a danger for 802.11 WLANs? - Solution evil twin access point what is an evil twin access point? - Solution a PC that has software to allow it to masquerade as an access point In what two types of attacks can the evil twin engage? - Solution Capturing credential transmission and key, and sending packets of its own Are evil twin attacks frequent? - Solution Yes Where are they the most frequently encountered? - Solution In public hot spots What type of devices could be used to flood the transmission frequency for a WLAN? - Solution common household items such as baby monitors, cordless phones, or Bluetooth devices to interfere with an 802.11 network What device could be used to identify a DoS flood if the entire frequency is being flooded by EMI? - Solution wireless spectrum analyzers What standard did the 802.3 Working Group create to extend 802.1X operation to WLANs with security for EAP? - Solution 802.11i What authentication method or methods does outer authentication use? - Solution Outer authentication uses SSL/TSL. What two extended EAP protocols are popular today? - Solution EAP/TLS and PEAP What was the first core wireless security standard? - Solution Wired equivalent privacy (WEP) What encryption algorithm does WEP use? - Solution RC4 What mistake did the 802.11 Working Group make in selecting the length of the IV? - Solution making IVs too short How long may WEP take to crack today? - Solution two or three minutes Should corporations today use WEP for security today? - Solution No. What does the Wi-Fi Alliance call 802.11i? - Solution WPA2 Despite its security weaknesses, why do many companies continue to use WPA instead of 802.11i? - Solution to avoid the cost of reconfiguring all access points and wireless clients to support WPA2 Why is it difficult to enforce a policy of using a different password at each site? - Solution because it is difficult for users to remember different passwords for different sites Why are password duration policies important? - Solution If passwords are not changed frequently, they will be able to use it for a long period of time. What are password resets? - Solution action taken by a help desk employee to create a new password for an account when the current password is lost or forgotten Why are password resets dangerous? - Solution susceptible to social engineering by an imposter What is the likely future of passwords? - Solution likely to be phased out in the fairly near future primarily because they are such a significant weakness What are one-time-password tokens? - Solution small devices with displays that have a number that changes frequently. What are USB tokens? - Solution a small device that plugs into a computer's USB port to identify the owner What is the advantage of USB tokens compared to cards? - Solution can be used to authenticate a user without the cost of having a smart card reader attached to the PC What is the attraction of proximity tokens? - Solution they do not require physical contact with a reader or USB port Why is it important to disable lost or stolen access devices? - Solution if not done, they can still be used by the thief What is a PIN (personal identification number)? - Solution a short number you type in manually to authenticate yourself What is biometric authentication? - Solution authentication based on biological metrics. On what two things about you is biometric authentication based? - Solution based upon something you are and something you do What is the major promise of biometrics? - Solution to make reusable passwords obsolete. What are key features? - Solution specific metrics extracted from the scanning data. What does the server do with the key features created by the enrollment scan? - Solution it uses these key features as the template for that user What is a template? - Solution the file entry containing key features from the enrollment process for a single individual. What is user access data? - Solution This is data collected during an access attempt scan What does a match index do? - Solution compares access key features with the template. In biometrics, what is a match? - Solution occurs when a match index meets the decision criteria What are false acceptance rates (FARs) and false rejection rates (FRRs)? - Solution These are the percentages of time there is a false acceptance or a false rejection from a scan For computer access, why is a false acceptance bad? - Solution because someone other than the authorized user, possibly an imposter, will gain access to the resource. Why is a false rejection bad? - Solution because a legitimate user is denied access to a resource. For watch lists of criminals, what is a false acceptance? - Solution an innocent person is identified as a criminal. What is failure to enroll? - Solution something that occurs if a system will not enroll a user