Security best practices in GCP - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ security

intermediate

Identify the least privilege principle in IAM roles

You have a Google Cloud project with multiple users. Which IAM role assignment best follows the least privilege principle?

A Assign the 'Viewer' role to users who only need to read resources.

B Assign the 'Owner' role to all users for full access.

C Assign the 'Editor' role to users who only need to deploy applications.

D Assign the 'Storage Admin' role to users who manage Compute Engine instances.

💡 Hint

Think about giving users only the permissions they need to do their job.

The 'Viewer' role grants read-only access, which is the minimum needed for users who only need to see resources. Assigning broader roles like 'Owner' or 'Editor' gives unnecessary permissions, violating least privilege.

❓ Architecture

intermediate

Choosing the best network security setup

You want to protect your Google Cloud VM instances from unauthorized internet access. Which setup provides the best security?

A Place VMs in a public subnet with firewall rules allowing all traffic.

B Assign external IPs to VMs and disable firewall rules.

C Use default network with no firewall rules.

D Place VMs in a private subnet with no external IPs and use Cloud NAT for outbound internet access.

💡 Hint

Think about how to keep VMs unreachable from the internet but still allow them to access the internet if needed.

Placing VMs in a private subnet without external IPs prevents inbound internet traffic. Using Cloud NAT allows outbound internet access securely. Other options expose VMs to the internet or lack firewall protection.

❓ Configuration

advanced

Detecting misconfigured Cloud Storage bucket permissions

Which of the following Cloud Storage bucket IAM policies will publicly expose the bucket contents?

A {"bindings": [{"role": "roles/storage.admin", "members": ["group:[e-mail]"]}]}

B {"bindings": [{"role": "roles/storage.objectViewer", "members": ["user:[e-mail]"]}]}

C {"bindings": [{"role": "roles/storage.objectViewer", "members": ["allUsers"]}]}

D {"bindings": [{"role": "roles/storage.objectCreator", "members": ["serviceAccount:[e-mail]"]}]}

💡 Hint

Look for the member that allows anyone on the internet access.

The member 'allUsers' means anyone on the internet can view objects in the bucket, making it public. Other members restrict access to specific users or service accounts.

❓ service_behavior

advanced

Understanding Cloud KMS key rotation impact

You rotate a Cloud KMS key used to encrypt data in Cloud Storage. What happens to the data encrypted with the old key version?

A Data encrypted with old key versions remains accessible and can be decrypted.

B Data encrypted with old key versions is deleted after key rotation.

C Data encrypted with old key versions is automatically re-encrypted with the new key version.

D Data encrypted with old key versions becomes unreadable immediately.

💡 Hint

Think about how key versions work in encryption.

Cloud KMS keeps old key versions active for decryption. Rotating a key creates a new version for encryption, but old data remains decryptable with previous versions.

🧠 Conceptual

expert

Analyzing the effect of enabling VPC Service Controls

You enable VPC Service Controls around your Google Cloud project. Which of the following is a direct effect of this action?

A It automatically encrypts all data at rest with customer-managed keys.

B It prevents data exfiltration by restricting access to services from outside the defined perimeter.

C It disables all firewall rules in the VPC network.

D It allows unrestricted access to Cloud Storage buckets within the project.

💡 Hint

Consider what VPC Service Controls are designed to protect against.

VPC Service Controls create a security perimeter that restricts access to Google Cloud services, preventing data from being accessed or moved outside the perimeter, thus reducing data exfiltration risks.

Practice

1. Which of the following is a key security best practice when managing access to Google Cloud resources?

easy

A. Give all users owner permissions for convenience

B. Assign the least privilege necessary using IAM roles

C. Share your service account keys publicly

D. Disable all logging to improve performance

Solution

1. Step 1: Understand IAM role assignment

   IAM roles control what users can do. Assigning least privilege means giving only the permissions needed.

2. Step 2: Evaluate options for security

   Giving owner permissions broadly or sharing keys publicly risks unauthorized access. Disabling logging hides important audit info.

3. Final Answer:

   Assign the least privilege necessary using IAM roles -> Option B

4. Quick Check:

   Least privilege = Assign minimal permissions [OK]

Hint: Always give only needed permissions, never more [OK]

Common Mistakes:

• Giving broad permissions for convenience
• Sharing keys or credentials publicly
• Disabling audit logs

2. Which of the following is the correct way to encrypt data in Google Cloud using Cloud KMS?

easy

A. Use Cloud KMS to generate encryption keys and encrypt data with those keys

B. Store encryption keys in plaintext in Cloud Storage

C. Encrypt data manually without using Cloud KMS

D. Disable encryption to improve speed

Solution

1. Step 1: Understand Cloud KMS role

   Cloud KMS manages encryption keys securely and helps encrypt/decrypt data safely.

2. Step 2: Evaluate encryption methods

   Storing keys in plaintext or disabling encryption risks data exposure. Manual encryption is error-prone.

3. Final Answer:

   Use Cloud KMS to generate encryption keys and encrypt data with those keys -> Option A

4. Quick Check:

   Cloud KMS = Secure key management [OK]

Hint: Always use Cloud KMS for key management and encryption [OK]

Common Mistakes:

• Storing keys unencrypted
• Skipping encryption for speed
• Encrypting data without key management

3. Consider this IAM policy snippet in JSON format:

{
  "bindings": [
    {
      "role": "roles/storage.objectViewer",
      "members": ["user:[e-mail]"]
    }
  ]
}

What permission does Alice have on the storage bucket?

medium

A. She can upload and delete objects

B. She has no access

C. She can only view objects

D. She can manage bucket settings

Solution

1. Step 1: Identify the role assigned

   The role is roles/storage.objectViewer, which grants read-only access to objects.

2. Step 2: Understand permissions of the role

   This role allows viewing objects but not uploading, deleting, or managing bucket settings.

3. Final Answer:

   She can only view objects -> Option C

4. Quick Check:

   objectViewer = read-only access [OK]

Hint: Viewer roles allow read-only access, no changes [OK]

Common Mistakes:

• Confusing viewer with editor or owner roles
• Assuming upload/delete permissions
• Ignoring role details

4. You have a service account key stored in a public GitHub repository. What is the best immediate action to secure your Google Cloud environment?

medium

A. Change the project name to confuse attackers

B. Ignore it since the key is not used

C. Share the key with your team for transparency

D. Delete the exposed key and create a new one

Solution

1. Step 1: Recognize the risk of exposed keys

   Publicly exposed keys can be used by attackers to access resources.

2. Step 2: Take immediate action to revoke and replace keys

   Deleting the exposed key and creating a new one prevents unauthorized access.

3. Final Answer:

   Delete the exposed key and create a new one -> Option D

4. Quick Check:

   Exposed keys = revoke immediately [OK]

Hint: Revoke exposed keys immediately to prevent breaches [OK]

Common Mistakes:

• Ignoring exposed keys
• Changing unrelated settings
• Sharing keys openly

5. You want to enforce that all data stored in Cloud Storage buckets is encrypted with customer-managed keys (CMKs) using Cloud KMS. Which combination of steps ensures this security best practice?

hard

A. Create a Cloud KMS key ring and key, then configure the bucket to use this key for default encryption

B. Store keys in a Compute Engine instance and manually encrypt files before upload

C. Use Google-managed encryption only and disable Cloud KMS

D. Encrypt files locally and upload without bucket encryption settings

Solution

1. Step 1: Create a Cloud KMS key ring and key

   This provides a customer-managed key to control encryption.

2. Step 2: Configure the Cloud Storage bucket to use the CMK for default encryption

   This ensures all objects are encrypted automatically with your key.

3. Final Answer:

   Create a Cloud KMS key ring and key, then configure the bucket to use this key for default encryption -> Option A

4. Quick Check:

   CMK + bucket default encryption = secure data [OK]

Hint: Use CMK with bucket default encryption for strong control [OK]

Common Mistakes:

• Relying only on Google-managed keys
• Encrypting manually without bucket settings
• Storing keys insecurely