CompTIA SY0-401 Free Practice Questions

Answer: B,C,F 

Explanation: 

B: Triple DES (3DES) is the common name for the Triple Data Encryption Algorithm (TDEA or Triple DEA) symmetric-key block cipher, which applies the Data Encryption Standard (DES) cipher algorithm three times to each data block. 

C: Advanced Encryption Standard (AES) is a block cipher that has replaced DES as the current standard, and it uses the Rijndael algorithm. It was developed by Joan Daemen and Vincent Rijmen. AES is the current product used by U.S. governmental agencies. 

F: Blowfish is an encryption system invented by a team led by Bruce Schneier that performs a 64-bit block cipher at very fast speeds. 

Answer: C 

Explanation: 

Once risks has been identified and assessed then there are five possible actions that should be taken. These are: Risk avoidance, Risk transference, Risk mitigation, Risk deterrence and Risk acceptance. Anytime you engage in steps to reduce risk, you are busy with risk mitigation and implementing IT security policy is a risk mitigation strategy. 

Answer: D 

Explanation: 

Most intrusion detection systems (IDS) are what is known as signature-based. This means that they operate in much the same way as a virus scanner, by searching for a known identity - or signature - for each specific intrusion event. And, while signature-based IDS is very efficient at sniffing out known s of attack, it does, like anti-virus software, depend on receiving regular signature updates, to keep in touch with variations in hacker technique. In other words, signature-based IDS is only as good as its database of stored signatures. Any organization wanting to implement a more thorough - and hence safer - solution, should consider what we call anomaly-based IDS. By its nature, anomaly-based IDS is a rather more complex creature. In network traffic terms, it captures all the headers of the IP packets running towards the network. From this, it filters out all known and legal traffic, including web traffic to the organization's web server, mail traffic to and from its mail server, outgoing web traffic from company employees and DNS traffic to and from its DNS server. 

There are other equally obvious advantages to using anomaly-based IDS. For example, because it detects any traffic that is new or unusual, the anomaly method is particularly good at identifying sweeps and probes towards network hardware. It can, therefore, give early warnings of potential intrusions, because probes and scans are the predecessors of all attacks. And this applies equally to any new service installed on any item of hardware - for example, Telnet deployed on a network router for maintenance purposes and forgotten about when the maintenance was finished. This makes anomaly-based IDS perfect for detecting anything from port anomalies and web anomalies to mis-formed attacks, where the URL is deliberately mis-typed. 

Answer: D 

Explanation: 

Patch management is the process of maintaining the latest source code for applications and operating systems by applying the latest vendor updates. This helps protect a systems from newly discovered attacks and vulnerabilities. A part of patch management is testing the effects of vendor updates on a test system first to ensure that the updates do not have detrimental effects on the system, and, should the updates have no detrimental effects on the test systems, backing up the production systems before applying the updates on a production system. 

Answer: C 

Explanation: 

A policy that states employees should use their vacation time in a staggered schedule is a way of employing mandatory vacations. A mandatory vacation policy requires all users to take time away from work while others step in and do the work of that employee on vacation. This will afford the CSO the opportunity to see who is using the company assets responsibly and who is abusing it. 

Answer: B 

Explanation: 

Load balancing is a way of providing high availability by splitting the workload across multiple computers. 

Answer: A 

Explanation: 

Secure Sockets Layer (SSL) is used to establish a secure communication connection between two TCP-based machines. Transport Layer Security (TLS) is a security protocol that expands upon SSL. Many industry analysts predict that TLS will replace SSL in the future. TLS 1.0 was first defined in RFC 2246 in January 1999 as an upgrade of SSL Version 3.0. As of February 2015, the latest versions of all major web browsers support TLS 1.0, 1.1, and 1.2, have them enabled by default. 

Answer: B 

Explanation: 

CAs can be either private or public, with VeriSign being one of the best known of the public variety. Many operating system providers allow their systems to be configured as CA systems. 

These CA systems can be used to generate internal certificates that are used within a business or in large external settings. The process provides certificates to the users. Since the user in question has been re-issued a smart card, the user must receive a new certificate by the CA to allow the user to send digitally signed email. This is achieved by publishing the new certificates to the global address list. 

Answer: C 

Explanation: 

The certificates of the leaving employees must be made unusable. This is done by revoking them. 

The revoke certificates end up in the CRL. 

Note: The CRL (Certificate revocation list) is exactly what its name implies: a list of subscribers 

paired with digital certificate status. The list enumerates revoked certificates along with the 

reason(s) for revocation. The dates of certificate issue, and the entities that issued them, are also 

included. In addition, each list contains a proposed date for the next release. 

Answer: B 

Explanation: 

The username should be just a username; instead we can see it’s a long line of text with an HTTP command in it. This is an example of a buffer overflow attack. A buffer overflow occurs when a program or process tries to store more data in a buffer (temporary data storage area) than it was intended to hold. Since buffers are created to contain a finite amount of data, the extra information - which has to go somewhere - can overflow into adjacent buffers, corrupting or overwriting the valid data held in them. Although it may occur accidentally through programming error, buffer overflow is an increasingly common type of security attack on data integrity. In buffer overflow attacks, the extra data may contain codes designed to trigger specific actions, in effect sending new instructions to the attacked computer that could, for example, damage the user's files, change data, or disclose confidential information. Buffer overflow attacks are said to have arisen because the C programming language supplied the framework, and poor programming practices supplied the vulnerability. 

Answer: B 

Explanation: 

Single-factor authentication (SFA) is a process for securing access to a given system by identifying the party requesting access via a single category of credentials. In this case, the network administrator makes use of an RFID card to access the datacenter, a key to access the server rack, and a username and password to access a server. 

Answer: A 

Explanation: 

Business impact analysis (BIA) is the process of evaluating all of the critical systems in an organization to define impact and recovery plans. BIA isn’t concerned with external threats or vulnerabilities; the analysis focuses on the impact a loss would have on the organization. A BIA comprises the following: identifying critical functions, prioritizing critical business functions, calculating a timeframe for critical systems loss, and estimating the tangible impact on the organization. 

Answer: A 

Explanation: 

A host-based IDS (HIDS) is an intrusion detection system that runs as a service on a host computer system. It is used to monitor the machine logs, system events, and application activity for signs of intrusion. It is useful for detecting attacks that originate outside the organization as well as attacks by internal users logged on to the system. 

Answer: D 

Explanation: 

In computer science, session hijacking, sometimes also known as cookie hijacking is the exploitation of a valid computer session—sometimes also called a session key—to gain unauthorized access to information or services in a computer system. In particular, it is used to refer to the theft of a magic cookie used to authenticate a user to a remote server. It has particular relevance to web developers, as the HTTP cookies used to maintain a session on many web sites can be easily stolen by an attacker using an intermediary computer or with access to the saved cookies on the victim's computer. 

Answer: C 

Explanation: 

Within Microsoft Windows, you have the ability to put signs (in the form of onscreen pop-up banners) that appear before the login telling similar information—authorized access only, violators will be prosecuted, and so forth. Such banners convey warnings or regulatory information to the user that they must “accept” in order to use the machine or network. You need to make staff aware that they may legally be prosecuted and a message is best given via a banner so that all staff using workstation will get notification.