adplus-dvertising

Welcome to the Deciphering File Formats MCQs Page

Dive deep into the fascinating world of Deciphering File Formats with our comprehensive set of Multiple-Choice Questions (MCQs). This page is dedicated to exploring the fundamental concepts and intricacies of Deciphering File Formats, a crucial aspect of Reverse Engineering. In this section, you will encounter a diverse range of MCQs that cover various aspects of Deciphering File Formats, from the basic principles to advanced topics. Each question is thoughtfully crafted to challenge your knowledge and deepen your understanding of this critical subcategory within Reverse Engineering.

frame-decoration

Check out the MCQs below to embark on an enriching journey through Deciphering File Formats. Test your knowledge, expand your horizons, and solidify your grasp on this vital area of Reverse Engineering.

Note: Each MCQ comes with multiple answer choices. Select the most appropriate option and test your understanding of Deciphering File Formats. You can click on an option to test your knowledge before viewing the solution for a MCQ. Happy learning!

Deciphering File Formats MCQs | Page 4 of 9

Explore more Topics under Reverse Engineering

Q31.
Why is it important to establish which system (and other) services the program utilizes in Cryptex?

a.

In order to track Cryptex’s I/O accesses

b.

In order to decrypt the .crx file format

c.

In order to get an overview of how Cryptex works

d.

In order to observe the encrypted data

Discuss
Answer: (a).In order to track Cryptex’s I/O accesses Explanation:Establishing which system (and other) services the program utilizes is critical because in order to track Cryptex’s I/O accesses (which is what you’re going to have to do in order to find the logic that generates and deciphers .crx files) you’re going to have to place breakpoints on these function calls.
Q32.
Why is it difficult to decipher a file format by merely observing the data?

a.

The file format is encrypted

b.

The file format does not contain any recognizable patterns

c.

The file format intentionally hides its contents

d.

All of the above

Discuss
Answer: (b).The file format does not contain any recognizable patterns Explanation:Even with programs that don’t intentionally hide the contents of their file formats, it is often very difficult to decipher a file format by merely observing the data.
Q33.
What does the import list reveal about Cryptex.exe?

a.

It uses direct calls into Win32 File I/O APIs.

b.

It uses the Windows Crypto API.

c.

It statically links with other libraries.

d.

All of the above.

Discuss
Answer: (d).All of the above. Explanation:The import list reveals that Cryptex.exe uses direct calls into Win32 File I/O APIs and the Windows Crypto API, as well as the fact that it may statically link with other libraries.
Q34.
What is the Windows Crypto API?

a.

A library for debugging software.

b.

A cryptographic library that provides support for CSPs.

c.

A generic programming interface for Windows.

d.

An algorithm for decrypting data.

Discuss
Answer: (b).A cryptographic library that provides support for CSPs. Explanation:The Windows Crypto API is a cryptographic library that provides support for installable cryptographic service providers (CSPs) and can be used for encrypting and decrypting data using a variety of cryptographic algorithms.
Q35.
What is the benefit of Cryptex using the Windows Crypto API?

a.

It makes it easier to determine which encryption algorithms the program employs.

b.

It makes it harder to determine which encryption algorithms the program employs.

c.

It allows Cryptex to encrypt files without a key.

d.

It allows Cryptex to bypass Windows security protocols.

Discuss
Answer: (a).It makes it easier to determine which encryption algorithms the program employs. Explanation:The fact that Cryptex uses the Crypto API can be seen as good news because it means that it is going to be quite trivial to determine which encryption algorithms the program employs and how it produces the encryption keys.
Q36.
What is the purpose of obtaining a list of imported functions?

a.

To determine which system services the program utilizes.

b.

To track the program's I/O accesses.

c.

To get an overview of the program and how it works.

d.

All of the above.

Discuss
Answer: (d).All of the above. Explanation:Obtaining a list of imported functions can provide an overview of how the program works, establish which system services the program utilizes, and help track the program's I/O accesses.
Q37.
What is the easiest way to check Cryptex's password verification process?

a.

Create an archive

b.

Start Cryptex in a debugger

c.

Type in the correct password

d.

Trace back from printf call

Discuss
Answer: (b).Start Cryptex in a debugger Explanation:The easiest way to go about checking Cryptex's password verification process is to start Cryptex in a debugger, feeding it with an incorrect password, and catch the place in the code where Cryptex notifies the user that a bad password has been supplied.
Q38.
Which runtime library function does Cryptex use for printing messages to the console window?

a.

CryptEncrypt

b.

CreateFile

c.

ReadFile

d.

printf

Discuss
Answer: (d).printf Explanation:Cryptex uses the printf function from MSVCR71.DLL runtime library for printing messages to the console window.
Q39.
What does the presence of the printf function in the runtime library list tell you?

a.

It tells you how Cryptex stores the passwords

b.

It tells you how Cryptex encrypts and decrypts data

c.

It tells you how Cryptex catches moments where it prints certain messages to the console window

d.

It tells you how Cryptex links with other libraries

Discuss
Answer: (c).It tells you how Cryptex catches moments where it prints certain messages to the console window Explanation:The presence of the printf function in the runtime library list tells you that it is used for printing messages to the console window and you can catch moments where Cryptex prints certain messages to the console window.
Q40.
Which DLL module reveals that Cryptex apparently uses direct calls into Win32 File I/O APIs such as CreateFile, ReadFile, WriteFile, etc.?

a.

KERNEL32.dll

b.

MSVCR71.DLL

c.

ADVAPI32.dll

d.

None of the above

Discuss
Answer: (a).KERNEL32.dll Explanation:The entries in KERNEL32.dll are highly informative because they're telling us that Cryptex apparently uses direct calls into Win32 File I/O APIs such as CreateFile, ReadFile, WriteFile, etc.
Page 4 of 9

Suggested Topics

Are you eager to expand your knowledge beyond Reverse Engineering? We've curated a selection of related categories that you might find intriguing.

Click on the categories below to discover a wealth of MCQs and enrich your understanding of Computer Science. Happy exploring!

Object Oriented Programming Using C++

Enhance your programming skills with our MCQs on Object Oriented Programming using...

Object Oriented Programming

Enhance your coding skills with our Object Oriented Programming MCQs. Understand...

Web Technologies

Master the building blocks of the web with our Web Technologies MCQs. From HTML and...

C# programming

Hone your skills in the C# language with our MCQs. Understand data types, operators,...

Cryptography and Network Security

Secure your knowledge of information security with our Cryptography and Network...

PHP

Venture into server-side scripting with our PHP MCQs. Cover everything from syntax...

Internet of Things (IoT)

Discover how devices communicate with each other in the smart world with our IoT...

MATLAB

Hone your computational mathematics skills with our MATLAB MCQs. Understand...

UNIX

Become proficient with the Unix operating system using our UNIX MCQs. Learn about...