Secure Code Review (SCR) : A6 — Sensitive Data Exposure

Sensitive Data Exposure is a critical security concern that occurs when an application does not adequately protect sensitive information. This can include passwords, credit card numbers, health records, personal information, and more. If attackers gain access to this data, they can commit fraud, identity theft, and other malicious activities.

In this blog, we will explore the concept of Sensitive Data Exposure, provide examples, and offer a comprehensive checklist for identifying this vulnerability during a secure code review.

Understanding Sensitive Data Exposure

Sensitive Data Exposure happens when an application fails to adequately protect sensitive information. This can occur in various ways, such as:

• Transmitting sensitive data over an insecure connection.
• Storing sensitive data in plaintext or using weak encryption.
• Exposing sensitive data through URLs, logs, or error messages.
• Failing to properly authenticate or authorize access to sensitive data.

For example, an e-commerce site that transmits credit card information over an unencrypted HTTP connection is vulnerable to eavesdropping, allowing attackers to intercept and steal credit card details.

Identifying Sensitive Data Exposure in Code Review

During a secure code review, it’s essential to identify places where sensitive data might be exposed. Here’s what to look for:

1. Insecure Data Transmission: Look for instances where sensitive data is transmitted over insecure channels, such as HTTP instead of HTTPS.
2. Weak Encryption or Plaintext Storage: Check for sensitive data that is stored in plaintext or encrypted using weak or outdated algorithms.
3. Exposure in URLs or Logs: Look for sensitive data that is included in URLs, logs, or error messages.
4. Lack of Proper Access Controls: Check for instances where sensitive data is accessible without proper authentication or authorization.

Secure Code Review Checklist for Sensitive Data Exposure

Here’s a checklist to follow when reviewing code for Sensitive Data Exposure:

1. Review Data Transmission: Check that sensitive data is transmitted over secure channels, such as HTTPS.
2. Analyze Data Storage: Ensure that sensitive data is stored securely, using strong encryption algorithms and secure key management practices.
3. Check for Data in URLs and Logs: Look for sensitive data that might be exposed in URLs, logs, or error messages.
4. Review Access Controls: Ensure that proper authentication and authorization controls are in place to protect access to sensitive data.
5. Analyze Password Policies: Check that strong password policies are enforced and that passwords are stored securely.
6. Review Data Masking: Ensure that sensitive data is masked or truncated when displayed, such as showing only the last four digits of a credit card number.
7. Check for Secure Data Deletion: Ensure that sensitive data is securely deleted when no longer needed.

Mitigating Sensitive Data Exposure

To prevent Sensitive Data Exposure, follow these best practices:

1. Use Secure Connections: Always transmit sensitive data over secure channels, such as HTTPS.
2. Encrypt Sensitive Data: Use strong encryption algorithms and secure key management practices to protect sensitive data at rest.
3. Avoid Exposure in URLs and Logs: Never include sensitive data in URLs, logs, or error messages.
4. Implement Strong Access Controls: Use proper authentication and authorization controls to restrict access to sensitive data.
5. Enforce Strong Password Policies: Require strong passwords and store them securely using proper hashing and salting techniques.
6. Mask or Truncate Displayed Data: Mask or truncate sensitive data when displayed to minimize exposure.
7. Securely Delete Data: Implement secure deletion practices for sensitive data when it is no longer needed.

In conclusion, Sensitive Data Exposure is a serious threat that can lead to significant harm if not properly addressed. By conducting a thorough secure code review and following the best practices outlined above, you can significantly reduce the risk of exposing sensitive data in your application. Regular monitoring and auditing are also essential to maintaining ongoing data protection.

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