Password storage best practices in Flask - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to hash a password using Werkzeug in Flask.

Flask

from werkzeug.security import [1]

hashed_password = [1]('mysecretpassword')

Drag options to blanks, or click blank then click option'

Agenerate_password_hash

Bcheck_password_hash

Chash_password

Dencrypt_password

Attempts:

3 left

💡 Hint

Common Mistakes

Using check_password_hash instead of generate_password_hash

Trying to encrypt password directly without hashing

Use generate_password_hash to create a secure hash of the password.

2fill in blank

medium

Complete the code to verify a password against its hash.

Flask

from werkzeug.security import check_password_hash

is_valid = check_password_hash([1], 'user_input_password')

Drag options to blanks, or click blank then click option'

Apassword_hash

Buser_password

Cplain_password

Dhashed_password

Attempts:

3 left

💡 Hint

Common Mistakes

Passing the plain password instead of the hashed password

Confusing argument order

The first argument to check_password_hash must be the stored hashed password.

3fill in blank

hard

Fix the error in the code to properly hash a password with salt.

Flask

hashed = generate_password_hash('mypassword', method=[1])

Drag options to blanks, or click blank then click option'

A'sha256'

B'plain'

C'bcrypt'

D'md5'

Attempts:

3 left

💡 Hint

Common Mistakes

Using insecure hash methods like md5 or sha256

Using 'plain' which does not hash

Use 'bcrypt' as the method for strong salted hashing.

4fill in blank

hard

Fill both blanks to create a dictionary comprehension that stores usernames with their hashed passwords.

Flask

user_hashes = { [1]: generate_password_hash([2]) for [1], [2] in users.items() }

Drag options to blanks, or click blank then click option'

Ausername

Bpassword

Cuser

Dpwd

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing variable names or using undefined names

Hashing the username instead of the password

Use username as key and hash the password value.

5fill in blank

hard

Fill all three blanks to check a password and print a message accordingly.

Flask

if check_password_hash([1], [2]):
    print([3])
else:
    print('Invalid password')

Drag options to blanks, or click blank then click option'

Astored_hash

Binput_password

C'Access granted!'

D'Welcome!'

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping the order of arguments in check_password_hash

Printing the wrong success message

Check the stored hash against the input password and print 'Access granted!' if valid.

Practice

1. Why should you never store plain text passwords directly in your Flask application's database?

easy

A. Because plain text passwords can be easily stolen if the database is compromised.

B. Because plain text passwords take up more space than hashed passwords.

C. Because Flask does not support storing plain text passwords.

D. Because hashed passwords are faster to compare than plain text passwords.

Solution

1. Step 1: Understand password security risks

   Storing plain text passwords means if someone hacks the database, they get all user passwords directly.

2. Step 2: Importance of hashing

   Hashing transforms passwords into unreadable strings, protecting user data even if the database leaks.

3. Final Answer:

   Because plain text passwords can be easily stolen if the database is compromised. -> Option A

4. Quick Check:

   Password safety = Avoid plain text storage [OK]

Hint: Never store passwords as plain text, always hash first [OK]

Common Mistakes:

• Thinking hashing is optional
• Believing plain text is safe if database is secure
• Confusing hashing with encryption

2. Which of the following is the correct way to hash a password using Werkzeug in Flask?

easy

A. hashed = make_password(password)

B. hashed = generate_password_hash(password)

C. hashed = password_hash(password)

D. hashed = hash_password(password)

Solution

1. Step 1: Recall Werkzeug's hashing function

   Werkzeug provides generate_password_hash to hash passwords securely.

2. Step 2: Identify correct function usage

   The correct function call is generate_password_hash(password), other options are invalid or non-existent.

3. Final Answer:

   hashed = generate_password_hash(password) -> Option B

4. Quick Check:

   Use generate_password_hash() to hash passwords [OK]

Hint: Use generate_password_hash() from Werkzeug to hash passwords [OK]

Common Mistakes:

• Using non-existent functions like hash_password
• Confusing hashing with encryption functions
• Trying to hash passwords manually

3. What will the following Flask code output if the password check is correct?

from werkzeug.security import generate_password_hash, check_password_hash
hashed = generate_password_hash('secret123')
result = check_password_hash(hashed, 'secret123')
print(result)

medium

A. False

B. secret123

C. Error

D. True

Solution

1. Step 1: Understand generate_password_hash output

   This function creates a hashed string from 'secret123'.

2. Step 2: Check password correctness with check_password_hash

   It compares the hashed password with the plain text 'secret123' and returns True if they match.

3. Final Answer:

   True -> Option D

4. Quick Check:

   check_password_hash returns True if passwords match [OK]

Hint: check_password_hash returns True when password matches hash [OK]

Common Mistakes:

• Expecting the original password as output
• Confusing True/False return values
• Assuming check_password_hash modifies the hash

4. Identify the error in this Flask password check code:

from werkzeug.security import generate_password_hash, check_password_hash
hashed = generate_password_hash('mypassword')
if check_password_hash('mypassword', hashed):
    print('Access granted')

medium

A. The hashed and plain password arguments are reversed in check_password_hash.

B. generate_password_hash should not be used for hashing passwords.

C. The print statement should be outside the if block.

D. There is no error; the code works correctly.

Solution

1. Step 1: Check argument order in check_password_hash

   The first argument must be the hashed password, second is the plain password.

2. Step 2: Identify the reversed arguments

   The code passes plain password first and hash second, causing a logic error.

3. Final Answer:

   The hashed and plain password arguments are reversed in check_password_hash. -> Option A

4. Quick Check:

   check_password_hash(hash, password) order matters [OK]

Hint: Pass hashed first, plain password second to check_password_hash [OK]

Common Mistakes:

• Swapping arguments in check_password_hash
• Using generate_password_hash incorrectly
• Ignoring function argument order

5. You want to securely store user passwords in your Flask app and verify them on login. Which approach follows best practices?

hard

A. Store plain passwords in the database and compare them directly on login.

B. Encrypt passwords with a reversible method and decrypt them on login to compare.

C. Hash passwords with generate_password_hash before storing, then verify with check_password_hash during login.

D. Store passwords as plain text but log them only during login attempts.

Solution

1. Step 1: Understand secure password storage

   Passwords must be hashed before storing to prevent exposure if database leaks.

2. Step 2: Verify passwords securely on login

   Use check_password_hash to compare the stored hash with the login password safely.

3. Final Answer:

   Hash passwords with generate_password_hash before storing, then verify with check_password_hash during login. -> Option C

4. Quick Check:

   Hash before store, verify with check_password_hash [OK]

Hint: Hash before store, verify with check_password_hash on login [OK]

Common Mistakes:

• Storing or logging plain passwords
• Using reversible encryption instead of hashing
• Comparing plain passwords directly