Question

1. What are the three categories for capabilities and provide a description of each?
2. In Debian, the ping utility is installed by default with setuid bit turned on. What is the security risk of having this turned on? How could this risk be mitigated?

3. Filename: finance.txt

group: finngrp

users: finmgr, finmgr1

            Using setacl,

1. Give read permissions to finance.txt to fingrp
2. Give read and write permissions to finance.txt to finmgr
3. Remove the permissions for finmgr1

Answer 1

To specify permission settings using alphanumerical characters, you’ll need to define accessibility for the user/owner (u), group (g), and others (o).

Type the initial letter for each class, followed by the equal sign (=) and the first letter of the read (r), write (w) and/or execute (x) privileges.

To set a file, so it is public for reading, writing, and executing, the command is:

chmod u=rwx,g=rwx,o=rwx [file_name]

a and b Ans

chmod u=rw,g=r finance.txt

use a + or - (plus or minus sign) to add or remove permissions for a file respectively. Use an equals sign =, to specify new permissions and remove the old ones for the particular type of user(s).

You can use chmod letter where the letters are:

a (all (everyone)), u (user), g (group) and o (other).

c Ans

chmod u-rwx finance.txt