CompTIA Updated PT0-002 Exam Questions and Answers by omer

The /var/log/lastlog file is a log file that stores information about the last user to sign in to the server. This file stores information such as the username, IP address, and timestamp of the last user to sign in to the server. It can be used by a penetration tester to determine the identity of the last user who signed in to the web server, which can be helpful in identifying the user who may have set up the backdoors and other malicious activities.

The BEST passive method of obtaining the technical contacts for the website would be a WHOIS domain lookup. WHOIS is a protocol that provides information about registered domain names, such as the registration date, registrant's name and contact information, and the name servers assigned to the domain. By performing a WHOIS lookup, the penetration tester can obtain the contact information of the website's technical staff, which can be used to craft a convincing phishing email.

A dictionary can be used to store alphanumeric data that can be fed into scripts or programs as input to penetration-testing tools. A dictionary is a collection of key-value pairs that can be accessed by using the keys. For example, a dictionary can store usernames and passwords, or IP addresses and hostnames, that can be used as input for brute-force or reconnaissance tools.

data structures are used to store data in an organized form, and some data structures are more efficient and suitable for certain operations than others. For example, hash tables, skip lists and jump lists are some dictionary data structures that can insert and access elements efficiently3.

For string comparison, there are different algorithms that can measure how similar two strings are, such as Levenshtein distance, Hamming distance or Jaccard similarity4. Some of these algorithms can be implemented using data structures such as arrays or hashtables5.