Which of the following changes should the team make to line 3 of the script?

A penetration testing team wants to conduct DNS lookups for a set of targets provided by the client.

The team crafts a Bash script for this task. However, they find a minor error in one line of the script:

1 #!/bin/bash

2 for i in $(cat example.txt); do

3 curl $i

4 done

Which of the following changes should the team make to line 3 of the script?
A . resolvconf $i
B . rndc $i
C . systemd-resolve $i
D . host $i

View Answer

Answer: D

Explanation:

Script Analysis:

Line 1: #!/bin/bash – This line specifies the script should be executed in the Bash shell.

Line 2: for i in $(cat example.txt); do – This line starts a loop that reads each line from the file example.txt and assigns it to the variable i.

Line 3: curl $i – This line attempts to fetch the content from the URL stored in i using curl. However, for DNS lookups, curl is inappropriate.

Line 4: done – This line ends the loop.

Error Identification:

The curl command is used for transferring data from or to a server, often used for HTTP requests,

which is not suitable for DNS lookups.

Correct Command:

To perform DNS lookups, the host command should be used. The host command performs DNS lookups and displays information about the given domain. Corrected Script:

Replace curl $i with host $i to perform DNS lookups on each target specified in example.txt.

Pentest

Reference: In penetration testing, DNS enumeration is a crucial step. It involves querying DNS servers to gather information about the target domain, which includes resolving domain names to IP addresses and vice versa.

Common tools for DNS enumeration include host, dig, and nslookup. The host command is particularly straightforward for simple DNS lookups.

By correcting the script to use host $i, the penetration testing team can effectively perform DNS lookups on the targets specified in example.txt.