IST 317
Fall, 2015
Test 1
NAME Fabunde Mamey
1.
Name and describe the three strategies people often use to make security decisions?
Rule Base- Rules that we followed based on what have been generally accepted and practiced
like lock the door of your car.
Relativists rule- Based on what others do. Example, I’ll have a stronger lock if I see my neighbor
with a lock.
Security Requirement- Rules that are based on what are required to prevent certain risks.
Explain the concept of the “hunter’s dilemma” and explain how it applies to computer
security.
The Hunter dilemma has to do with one hunter running faster than the others when they are
being chased by a bear or predator. The point is, if you cannot run faster than the bear, run faster
than you colleague so you can’t get caught.
2.
3.
Of the three strategies listed in Problem #2, which is the most appropriate according to
our author? Why?
The Relativists rule, because it is difficult for our system to not be bridged, so what we can do is
to make our system harder to be hacked as compared to our neighbors.
4.
What is one aspect of control that access control lists in Windows can manage that
Unix permission flags cannot?
a. Permissions for anyone other than the owner or group
b. Permissions for multiple users and groups
c. Permissions for the file owner’s group
d. None of the above
b. Permissions for multiple users and groups
5.
What is the difference between a white-hat hacker and a black-hat hacker?
A whit- hat hacker is one who is trained to prevent or track malicious treat or attacks, while a
black-hat hacker is a hacker who tries to attack systems.
6.
What is the purpose of the Unix “sudo” command? How does it improve security?
The purpose is to allow user run programs or do other tasks by changing the user identity to
another who has privileges to run certain tasks. It improves security by allowing only does with
the appropriate rights or privileges to carry on certain tasks.
7.
What is an example of a “security requirement”?
On is that all users change their default password when they first log in to organization’s
computer.
8.
Explain the role of control sections of memory vs data sections of memory.
The control section has computer instructions that do not change, unlike variables in a program.
The data section is used to store changeable data like variables in a program.
9.
Explain what happens when the CPU switches from one process to another.
The CPU pauses on the current process, saves its return address and start work on the other and
when it’s done, it uses the return address of the previous process to continue where it left.
This happens so fast that we think it’s running two processes simultaneously.
10.
Explain how the Morris worm works. Why is it referred to as an example of buffer
overflow?
It worked by using the finger command and inputting more data than required (filled it with lots
of Xs) in the control section that it overflowed the buffer and then when to the data
section. In which he changed the return address to a counter that started a shell program
that he Morris wrote.
It is referred to as an example buffer overflow because Morris used the vulnerability of the buffer
size to be exceeded or overflowed. He used that to run is worm program.
11.
Describe one technique that would have prevented the Morris worm from working.
One technique would be rejecting instructions in the data section of a program.
12.
Why is it good to control the “bootstrap” process during startup?
It is good because if it is not controlled. That could be vulnerability for malicious programs to
start while the computer boots.
13.
Describe the file access permissions of r, w, and x for the standard Unix operating
system.
R means a user can read file contents; w means user can write or make changes to a file; x means
a user can execute or run an executable file.
14.
What do the permissions of r, w, and x mean for a Unix directory?
r- user can list directory contents; w- make changes to directory, create new folders or files and
so on; x- N/A.
15.
What would the following Unix command do?
chmod 777 mydata
It gives read, write, and execute permission to the user, group and world for mydata.
16.
What are the default Unix file permissions that are used when a new file is created.
Read and write
17.
Describe the concept of the Windows ACL.
Windows ACL basically deals with setting permissions on objects or resources for individuals as
well as groups. This includes denying a subject certain privileges and granting him/her
others.
18.
If we create a Windows ACL for a file in which we deny all permissions to Jim, but we
grant all permissions to everyone, does Jim have any access to this file? Explain.
No, because deny overrides granted permissions; so even though she is considered as everyone,
she has already been denied certain privileges.
19.
Our text describes how a Trojan program can make secret data belonging to one user
visible to another unauthorized user. Explain how this can take place.
When an infected program is execute, the Trojan looks into confidential folders and make files in
that folder available to another using there permissions of the person who has the
program in common. It also uses the user rights to carry on these tasks.
20.
How does Windows concept of groups help in assigning access permissions to a user
account?
It greatly helps by adding users into a group and then setting permissions for that group. This
makes things much easier. An example is the faculty group in the Comp science
department.