File upload security in Cybersecurity - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to check the file extension before upload.

Cybersecurity

if filename.endswith([1]):
    print("File accepted")

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

A".jpg"

B".bat"

C".exe"

D".dll"

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing executable extensions like .exe or .bat which are unsafe.

Only files with the .jpg extension are accepted here to reduce risk.

2fill in blank

medium

Complete the code to limit the maximum file size to 5MB.

Cybersecurity

if file_size [1] 5 * 1024 * 1024:
    print("File size is acceptable")

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

A>

B==

C<=

D>=

Attempts:

3 left

💡 Hint

Common Mistakes

Using > or >= which would accept files larger than 5MB.

The file size should be less than or equal to 5MB to be accepted.

3fill in blank

hard

Fix the error in the code that checks for allowed MIME types.

Cybersecurity

allowed_types = ['image/png', 'image/jpeg']
if file_mime_type [1] allowed_types:
    print("MIME type allowed")

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

A==

Bnot in

C!=

Din

Attempts:

3 left

💡 Hint

Common Mistakes

Using == which compares to the whole list, not membership.

The in operator checks if the MIME type is in the allowed list.

4fill in blank

hard

Fill both blanks to safely save the uploaded file with a unique name.

Cybersecurity

import uuid
unique_name = str(uuid.[1]()) + [2] + file_extension
save_file(unique_name)

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Auuid4

B"_"

C"."

Duuid1

Attempts:

3 left

💡 Hint

Common Mistakes

Using uuid1 which is time-based and less random.

Joining with underscore instead of dot.

Using uuid4() generates a random unique ID, and "." joins the name and extension safely.

5fill in blank

hard

Fill all three blanks to create a dictionary comprehension filtering safe files by size and extension.

Cybersecurity

safe_files = {file: size for file, size in files.items() if file.endswith([1]) and size [2] [3]

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

A".png"

B<=

C5 * 1024 * 1024

D".exe"

Attempts:

3 left

💡 Hint

Common Mistakes

Using unsafe extensions like .exe.

Using > instead of <= for size.

This comprehension keeps files ending with .png and size less than or equal to 5MB.