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Q191. Which of the following risk concepts requires an organization to determine the number of failures per year? 

A. SLE 

B. ALE 

C. MTBF 

D. Quantitative analysis 

Answer:

Explanation: 

ALE is the annual loss expectancy value. This is a monetary measure of how much loss you could expect in a year. 


Q192. A network administrator wants to block both DNS requests and zone transfers coming from outside IP addresses. The company uses a firewall which implements an implicit allow and is currently configured with the following ACL applied to its external interface. 

PERMIT TCP ANY ANY 80 

PERMIT TCP ANY ANY 443 

Which of the following rules would accomplish this task? (Select TWO). 

A. Change the firewall default settings so that it implements an implicit deny 

B. Apply the current ACL to all interfaces of the firewall 

C. Remove the current ACL 

D. Add the following ACL at the top of the current ACL DENY TCP ANY ANY 53 

E. Add the following ACL at the bottom of the current ACL DENY ICMP ANY ANY 53 

F. Add the following ACL at the bottom of the current ACL DENY IP ANY ANY 53 

Answer: A,F 

Explanation: 

Implicit deny is the default security stance that says if you aren’t specifically granted access or privileges for a resource, you’re denied access by default. Implicit deny is the default response when an explicit allow or deny isn’t present. 

DNS operates over TCP and UDP port 53. TCP port 53 is used for zone transfers. These are zone file exchanges between DNS servers, special manual queries, or used when a response exceeds 512 bytes. UDP port 53 is used for most typical DNS queries. 


Q193. One of the most basic ways to protect the confidentiality of data on a laptop in the event the device is physically stolen is to implement which of the following? 

A. File level encryption with alphanumeric passwords 

B. Biometric authentication and cloud storage 

C. Whole disk encryption with two-factor authentication 

D. BIOS passwords and two-factor authentication 

Answer:

Explanation: Whole-disk encryption only provides reasonable protection when the system is fully powered off. to make the most of the defensive strength of whole-disk encryption, a long, complex passphrase should be used to unlock the system on bootup. Combining whole-disk encryption with two factor authentication would further increase protection. 


Q194. An encrypted message is sent using PKI from Sara, a client, to a customer. Sara claims she never sent the message. Which of the following aspects of PKI BEST ensures the identity of the sender? 

A. CRL 

B. Non-repudiation 

C. Trust models 

D. Recovery agents 

Answer:

Explanation: 

Nonrepudiation prevents one party from denying actions they carried out. This means that the identity of the email sender will not be repudiated. 


Q195. A company hired Joe, an accountant. The IT administrator will need to create a new account for 

Joe. The company uses groups for ease of management and administration of user accounts. 

Joe will need network access to all directories, folders and files within the accounting department. 

Which of the following configurations will meet the requirements? 

A. Create a user account and assign the user account to the accounting group. 

B. Create an account with role-based access control for accounting. 

C. Create a user account with password reset and notify Joe of the account creation. 

D. Create two accounts: a user account and an account with full network administration rights. 

Answer:

Explanation: 

Role-based Access Control is basically based on a user’s job description. When a user is assigned a specific role in an environment, that user’s access to objects is granted based on the required tasks of that role. The IT administrator should, therefore, create an account with role-based access control for accounting for Joe. 


Q196. RADIUS provides which of the following? 

A. Authentication, Authorization, Availability 

B. Authentication, Authorization, Auditing 

C. Authentication, Accounting, Auditing 

D. Authentication, Authorization, Accounting 

Answer:

Explanation: 

The Remote Authentication Dial In User Service (RADIUS) networking protocol offers centralized Authentication, Authorization, and Accounting (AAA) management for users who make use of a network service. It is for this reason that A, B, and C: are incorrect. 

References: http://en.wikipedia.org/wiki/RADIUS 


Q197. Timestamps and sequence numbers act as countermeasures against which of the following types of attacks? 

A. Smurf 

B. DoS 

C. Vishing 

D. Replay 

Answer:

Explanation: 

A replay attack (also known as playback attack) is a form of network attack in which a valid data transmission is maliciously or fraudulently repeated or delayed. This is carried out either by the originator or by an adversary who intercepts the data and retransmits it, possibly as part of a masquerade attack by IP packet substitution (such as stream cipher attack). 

For example: Suppose Alice wants to prove her identity to Bob. Bob requests her password as proof of identity, which Alice dutifully provides (possibly after some transformation like a hash function); meanwhile, Eve is eavesdropping on the conversation and keeps the password (or the hash). After the interchange is over, Eve (posing as Alice) connects to Bob; when asked for a proof of identity, Eve sends Alice's password (or hash) read from the last session, which Bob accepts thus granting access to Eve. 

Countermeasures: A way to avoid replay attacks is by using session tokens: Bob sends a one-time token to Alice, which Alice uses to transform the password and send the result to Bob (e.g. computing a hash function of the session token appended to the password). On his side Bob performs the same computation; if and only if both values match, the login is successful. Now suppose Eve has captured this value and tries to use it on another session; Bob sends a different session token, and when Eve replies with the captured value it will be different from Bob's computation. Session tokens should be chosen by a (pseudo-) random process. Otherwise Eve may be able to pose as Bob, presenting some predicted future token, and convince Alice to use that token in her transformation. Eve can then replay her reply at a later time (when the previously predicted token is actually presented by Bob), and Bob will accept the authentication. One-time passwords are similar to session tokens in that the password expires after it has been used or after a very short amount of time. They can be used to authenticate individual transactions in addition to sessions. The technique has been widely implemented in personal online banking systems. Bob can also send nonces but should then include a message authentication code (MAC), which Alice should check. Timestamping is another way of preventing a replay attack. Synchronization should be achieved using a secure protocol. For example Bob periodically broadcasts the time on his clock together with a MAC. When Alice wants to send Bob a message, she includes her best estimate of the time on his clock in her message, which is also authenticated. Bob only accepts messages for which the timestamp is within a reasonable tolerance. The advantage of this scheme is that Bob does not need to generate (pseudo-) random numbers, with the trade-off being that replay attacks, if 

they are performed quickly enough i.e. within that 'reasonable' limit, could succeed. 


Q198. A security administrator implements access controls based on the security classification of the data and need-to-know information. Which of the following BEST describes this level of access control? 

A. Implicit deny 

B. Role-based Access Control 

C. Mandatory Access Controls 

D. Least privilege 

Answer:

Explanation: 

Mandatory Access Control allows access to be granted or restricted based on the rules of classification. MAC also includes the use of need to know. Need to know is a security restriction where some objects are restricted unless the subject has a need to know them. 


Q199. Which of the following would be used when a higher level of security is desired for encryption key storage? 

A. TACACS+ 

B. L2TP 

C. LDAP 

D. TPM 

Answer:

Explanation: 

Trusted Platform Module (TPM) is a hardware-based encryption solution that is embedded in the system’s motherboard and is enabled or disable in BIOS. It helps with hash key generation and stores cryptographic keys, passwords, or certificates. 


Q200. Ann, a security analyst, is preparing for an upcoming security audit. To ensure that she identifies unapplied security controls and patches without attacking or compromising the system, Ann would use which of the following? 

A. Vulnerability scanning 

B. SQL injection 

C. Penetration testing 

D. Antivirus update 

Answer:

Explanation: 

A vulnerability scan is the process of scanning the network and/or I.T. infrastructure for threats and vulnerabilities. The threats and vulnerabilities are then evaluated in a risk assessment and the necessary actions taken to resolve and vulnerabilities. A vulnerability scan scans for known weaknesses such as missing patches or security updates. 

A vulnerability scan is the automated process of proactively identifying security vulnerabilities of computing systems in a network in order to determine if and where a system can be exploited and/or threatened. While public servers are important for communication and data transfer over the Internet, they open the door to potential security breaches by threat agents, such as malicious hackers. Vulnerability scanning employs software that seeks out security flaws based on a database of known flaws, testing systems for the occurrence of these flaws and generating a report of the findings that an individual or an enterprise can use to tighten the network's security.