Exercise 23: Cloud API Key Leakage and Exploitation

Objective:

Understand how exposed API keys can lead to unauthorized access to cloud services. Simulate an attacker discovering and exploiting leaked API keys and learn how to secure API keys using best practices like environment variables, secure vaults, and encryption.

---

Scenario:

An organization has accidentally exposed API keys in a public repository or left them improperly stored in plain text. Attackers discover these keys and use them to gain unauthorized access to cloud resources. Your goal is to simulate this scenario, demonstrate the risks, and provide mitigation strategies.

---

Lab Setup:

Prerequisites:

1. Access to a cloud platform:
   • AWS or Google Cloud.
2. Installed tools:
   • aws-cli (Installation Guide).
   • gcloud (Installation Guide).
   • git-secrets (Installation Guide).

---

Steps to Set Up the Lab:

1. Deploy a Cloud Service Using API Keys:
   • AWS:
     1. Navigate to API Gateway > Create API.
     2. Create a REST API and configure a test endpoint:
        • Resource Path: /test.
        • Method: GET.
        • Integration: Mock Integration (for simplicity).
     3. Deploy the API and enable API key usage:
        • Create an API key under Usage Plans.
        • Note the API key.
   • Google Cloud:
     1. Navigate to APIs & Services > Credentials > Create Credentials.
     2. Select API Key and note the generated key.
2. Simulate API Key Leakage:
   • Create a GitHub repository and push the API key accidentally:
     1. Initialize a Git repository:bashCopyEditgit init echo "API_KEY=YOUR_API_KEY" > .env git add .env git commit -m "Added API key" git remote add origin https://github.com/<your-username>/<your-repo>.git git push -u origin main
     2. Ensure the .env file contains the API key and is visible in the repository.
3. Discover the Leaked Key:
   • Use GitHub search or a public scanning tool to locate exposed keys:
     • Search syntax on GitHub:phpCopyEditAPI_KEY "<key-pattern>" repo:<your-username>/<your-repo>

---

Exercise: Exploiting the Leaked API Key

Objective:

Simulate an attacker using the leaked API key to exploit cloud services.

1. Access the API Using the Key:
   • AWS:bashCopyEditcurl -H "x-api-key: YOUR_API_KEY" https://<api-id>.execute-api.<region>.amazonaws.com/<stage>/test
   • Google Cloud:bashCopyEditcurl "https://<your-google-api-endpoint>?key=YOUR_API_KEY"
2. Test API Abuse:
   • Perform multiple requests using the leaked key to simulate abuse (e.g., brute force or high API call rates).
3. Simulate Key Misuse:
   • Use the API key to access unauthorized resources or gain insights about the cloud environment:
     • For AWS:bashCopyEditaws s3 ls --profile leaked-profile
4. Analyze Access Logs:
   • If monitoring tools are enabled (e.g., AWS CloudTrail or Google Cloud Logging), check for the attacker’s activity in logs.

---

Tools Required:

1. aws-cli or gcloud: For API interactions.
2. git-secrets: For detecting sensitive information in repositories.
3. curl: For testing API requests.

---

Deliverables:

1. Exploit Report:
   • Evidence of discovering and exploiting leaked API keys.
   • Logs or screenshots of unauthorized API access.
2. Recommendations for Mitigating API Key Leakage:
   • Steps to secure API keys and prevent accidental exposure.

---

Solution:

1. Identified Vulnerabilities:
   • Exposed API Key: API keys were publicly accessible in a GitHub repository.
   • Lack of Key Rotation: Leaked keys were not rotated, allowing prolonged access.
   • No Monitoring: No alerts were triggered for unusual API activity.
2. Consequences:
   • Unauthorized Access: Attackers used the key to access cloud resources.
   • Service Abuse: API abuse could lead to resource exhaustion or unexpected charges.
   • Data Breach: Exposed API keys could provide access to sensitive data.
3. Prevention Techniques:
   • Secure Key Storage:
     • Use environment variables or secret management tools (e.g., AWS Secrets Manager, HashiCorp Vault).
   • Prevent Key Leaks:
     • Use git-secrets to detect API keys before committing:bashCopyEditgit secrets --install git secrets --scan
   • Monitor API Usage:
     • Enable logging for API activity (e.g., AWS CloudTrail, Google Cloud Logging).
     • Configure alerts for unusual API usage patterns.
   • Implement Authentication:
     • Use OAuth or IAM-based authentication instead of static API keys.
   • Rotate Keys Regularly:
     • Implement a key rotation policy to minimize the impact of leaked keys.
   • Restrict API Key Scope:
     • Use least privilege to limit API key access to specific resources.

---

Conclusion:

This exercise demonstrates the risks of API key leakage and how attackers exploit exposed keys to access cloud services. By securing API keys, monitoring usage, and adopting key rotation policies, organizations can mitigate these risks and protect their cloud environments.