CompTIA Security+ Question K-21

Peter, the security administrator, has been notified by the IDS that the company website is under attack. Analysis of the web logs show the following string, indicating a user is trying to post a comment on the public bulletin board.
INSERT INTO message `
This is an example of which of the following?

A. XSS attack
B. XML injection attack
C. Buffer overflow attack
D. SQL injection attack

Answer: A

Explanation:
The tags indicate that script is being inserted. Cross-site scripting (XSS) is a type of computer security vulnerability typically found in Web applications. XSS enables attackers to inject client-side script into Web pages viewed by other users. Cross-site scripting uses known vulnerabilities in web-based applications, their servers, or plug-in systems on which they rely. Exploiting one of these, attackers fold malicious content into the content being delivered from the compromised site. When the resulting combined content arrives at the client-side web browser, it has all been delivered from the trusted source, and thus operates under the permissions granted to that system. By finding ways of injecting malicious scripts into web pages, an attacker can gain elevated access-privileges to sensitive page content, session cookies, and a variety of other information maintained by the browser on behalf of the user.

CompTIA Security+ Question K-1

Which of the following cryptographic related browser settings allows an organization to communicate securely?

A. SSL 3.0/TLS 1.0
B. 3DES
C. Trusted Sites
D. HMAC

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.

CompTIA Security+ Question J-94

Public keys are used for which of the following?

A. Decrypting wireless messages
B. Decrypting the hash of an electronic signature
C. Bulk encryption of IP based email traffic
D. Encrypting web browser traffic

Answer: B

Explanation:
The sender uses the private key to create a digital signature. The message is, in effect, signed with the private key. The sender then sends the message to the receiver. The receiver uses the public key attached to the message to validate the digital signature. If the values match, the receiver knows the message is authentic.

CompTIA Security+ Question J-40

Which of the following components of an all-in-one security appliance would MOST likely be configured in order to restrict access to peer-to-peer file sharing websites?

A. Spam filter
B. URL filter
C. Content inspection
D. Malware inspection

Answer: B

Explanation:
The question asks how to prevent access to peer-to-peer file sharing websites. You access a website by browsing to a URL using a Web browser or peer-to-peer file sharing client software. A URL filter is used to block URLs (websites) to prevent users accessing the website.

Incorrect Answer:

A: A spam filter is used for email. All inbound (and sometimes outbound) email is passed through the spam filter to detect spam emails. The spam emails are then discarded or tagged as potential spam according to the spam filter configuration. Spam filters do not prevent users accessing peer­to-peer file sharing websites.

C: Content inspection is the process of inspecting the content of a web page as it is downloaded.

The content can then be blocked if it doesn’t comply with the company’s web policy. Content-control software determines what content will be available or perhaps more often what content will be blocked. Content inspection does not prevent users accessing peer-to-peer file sharing websites (although it could block the content of the sites as it is downloaded).

D: Malware inspection is the process of scanning a computer system for malware. Malware inspection does not prevent users accessing peer-to-peer file sharing websites.

References: http://www.provision.ro/threat-management/web-application-security/url-filtering#pagei-1|pagep-1| Stewart, James Michael, CompTIA Security+ Review Guide, Sybex, Indianapolis, 2014, pp. 18, 19

CompTIA Security+ Question H-80

Which device monitors network traffic in a passive manner?

A. Sniffer
B. IDS
C. Firewall
D. Web browser

Answer: A

Explanation:
A sniffer is another name for a protocol analyzer. A protocol analyzer performs its function in a passive manner. In other words, computers on the network do not know that their data packets have been captured. A Protocol Analyzer is a hardware device or more commonly a software program used to capture network data communications sent between devices on a network. Capturing packets sent from a computer system is known as packet sniffing. Well known software protocol analyzers include Message Analyzer (formerly Network Monitor) from Microsoft and Wireshark (formerly Ethereal).

A sniffer (packet sniffer) is a tool that intercepts data flowing in a network. If computers are connected to a local area network that is not filtered or switched, the traffic can be broadcast to all computers contained in the same segment. This doesn’t generally occur, since computers are generally told to ignore all the comings and goings of traffic from other computers. However, in the case of a sniffer, all traffic is shared when the sniffer software commands the Network Interface Card (NIC) to stop ignoring the traffic. The NIC is put into promiscuous mode, and it reads communications between computers within a particular segment. This allows the sniffer to seize everything that is flowing in the network, which can lead to the unauthorized access of sensitive data. A packet sniffer can take the form of either a hardware or software solution. A sniffer is also known as a packet analyzer.

CompTIA Security+ Question H-60

A distributed denial of service attack can BEST be described as:

A. Invalid characters being entered into a field in a database application.
B. Users attempting to input random or invalid data into fields within a web browser application.
C. Multiple computers attacking a single target in an organized attempt to deplete its resources.
D. Multiple attackers attempting to gain elevated privileges on a target system.

Answer: C

Explanation:
A Distributed Denial of Service (DDoS) attack is an attack from several different computers targeting a single computer. One common method of attack involves saturating the target machine with external communications requests, so much so that it cannot respond to legitimate traffic, or responds so slowly as to be rendered essentially unavailable. Such attacks usually lead to a server overload.

A distributed denial-of-service (DDoS) attack occurs when multiple systems flood the bandwidth or resources of a targeted system, usually one or more web servers. Such an attack is often the result of multiple compromised systems (for example a botnet) flooding the targeted system with traffic. When a server is overloaded with connections, new connections can no longer be accepted. The major advantages to an attacker of using a distributed denial-of-service attack are that multiple machines can generate more attack traffic than one machine, multiple attack machines are harder to turn off than one attack machine, and that the behavior of each attack machine can be stealthier, making it harder to track and shut down. These attacker advantages cause challenges for defense mechanisms. For example, merely purchasing more incoming bandwidth than the current volume of the attack might not help, because the attacker might be able to simply add more attack machines. This after all will end up completely crashing a website for periods of time. Malware can carry DDoS attack mechanisms; one of the better-known examples of this was MyDoom. Its DoS mechanism was triggered on a specific date and time. This type of DDoS involved hardcoding the target IP address prior to release of the malware and no further interaction was necessary to launch the attack.

CompTIA Security+ Question G-38

In which of the following scenarios is PKI LEAST hardened?

A. The CRL is posted to a publicly accessible location.
B. The recorded time offsets are developed with symmetric keys.
C. A malicious CA certificate is loaded on all the clients.
D. All public keys are accessed by an unauthorized user.

Answer: C

Explanation:
A rogue Certification Authority (CA) certificate allows malicious users to impersonate any Web site on the Internet, including banking and e-commerce sites secured using the HTTPS protocol. A rogue CA certificate would be seen as trusted by Web browsers, and it is harmful because it can appear to be signed by one of the root CAs that browsers trust by default. A rogue Certification Authority (CA) certificate can be created using a vulnerability in the Internet Public Key Infrastructure (PKI) used to issue digital certificates for secure Web sites.

CompTIA Security+ Question F-75

A recent spike in virus detections has been attributed to end-users visiting www.compnay.com. The business has an established relationship with an organization using the URL of www.company.com but not with the site that has been causing the infections. Which of the following would BEST describe this type of attack?

A. Typo squatting
B. Session hijacking
C. Cross-site scripting
D. Spear phishing

Answer: A

Explanation:
Typosquatting, also called URL hijacking or fake url, is a form of cybersquatting, and possibly brandjacking which relies on mistakes such as typographical errors made by Internet users when inputting a website address into a web browser. Should a user accidentally enter an incorrect website address, they may be led to any URL (including an alternative website owned by a cybersquatter).

The typosquatter’s URL will usually be one of four kinds, all similar to the victim site address: (In the following, the intended website is “example.com”) A common misspelling, or foreign language spelling, of the intended site: exemple.com A misspelling based on typing errors: xample.com or examlpe.com A differently phrased domain name: examples.com A different top-level domain: example.org

Once in the typosquatter’s site, the user may also be tricked into thinking that they are in fact in the real site; through the use of copied or similar logos, website layouts or content.

CompTIA Security+ Question D-100

Peter, a security analyst, has been tasked with explaining the different types of malware to his colleagues. The two malware types that the group seems to be most interested in are botnets and viruses. Which of the following explains the difference between these two types of malware?

A. Viruses are a subset of botnets which are used as part of SYN attacks.
B. Botnets are a subset of malware which are used as part of DDoS attacks.
C. Viruses are a class of malware which create hidden openings within an OS.
D. Botnets are used within DR to ensure network uptime and viruses are not.

Answer: B

Explanation:
A botnet is a collection of Internet-connected programs communicating with other similar programs in order to perform tasks. This can be as mundane as keeping control of an Internet Relay Chat (IRC) channel, or it could be used to send spam email or participate in distributed denial-of-service attacks. The word botnet is a combination of the words robot and network. The term is usually used with a negative or malicious connotation. Computers can be co-opted into a botnet when they execute malicious software. This can be accomplished by luring users into making a drive-by download, exploiting web browser vulnerabilities, or by tricking the user into running a Trojan horse program, which may come from an email attachment. This malware will typically install modules that allow the computer to be commanded and controlled by the botnet’s operator. Many computer users are unaware that their computer is infected with bots. Depending on how it is written, a Trojan may then delete itself, or may remain present to update and maintain the modules.

CompTIA Security+ Question D-45

Which of the following policies is implemented in order to minimize data loss or theft?

A. PII handling
B. Password policy
C. Chain of custody
D. Zero day exploits

Answer: A

Explanation:
Although the concept of PII is old, it has become much more important as information technology and the Internet have made it easier to collect PII through breaches of internet security, network security and web browser security, leading to a profitable market in collecting and reselling PII. PII can also be exploited by criminals to stalk or steal the identity of a person, or to aid in the planning of criminal acts. Personally identifiable information (PII) is a catchall for any data that can be used to uniquely identify an individual. This data can be anything from the person’s name to a fingerprint (think biometrics), credit card number, or patient record. Thus a PII handling policy can be used to protect data.