Cryptography (CR7)

The card is related to weak configuration rather than missing encryption.

Scenario: Gunter's Exploitation of Flaws in Encryption Protocols

Imagine a scenario where Gunter intercepts or modifies encrypted data in transit, taking advantage of weak deployment or configuration of encryption protocols. This occurs due to:

1. Poor Deployment of Encryption Protocols: The application’s encrypted communication protocols are implemented improperly.
2. Weak Configuration: The settings for encrypted communications are not optimized, leaving vulnerabilities.
3. Invalid or Untrusted Certificates: The application uses certificates that are either invalid or not trusted by client systems.
4. Degradation of Communication Security: The system allows the encryption level to be downgraded to weaker or unencrypted states.

Example

Gunter targets an online service that uses encryption for data transmission. However, he discovers that the service’s SSL/TLS configuration is outdated, allowing him to exploit known vulnerabilities. Additionally, the service uses self-signed certificates, which are not properly validated, increasing the risk of man-in-the-middle attacks. Gunter leverages these weaknesses to intercept and decrypt the data being transmitted, modifying it before re-encryption and forwarding.

Threat Modeling

STRIDE

The primary applicable STRIDE categories for this scenario is Information Disclosure and Tampering.

Because Gunter can intercept and decrypt the data in transit due to weak protocol deployment, misconfigured SSL/TLS, or untrusted/invalid certificates. This is a confidentiality failure, but as he can also modify the encrypted data (MITM style, degrade the connection, or re-encrypt altered content), it also falls into Tampering, finally, if cryptographic signatures is used and can be faked, the Tampering can also lead to Spoofing.

What can go wrong?

Such vulnerabilities can lead to data interception, unauthorized access, and information tampering, potentially compromising user privacy and data integrity.

For more things that can go wrong, see the Common Attack Patterns related to this card in the table below.

What are we going to do about it?

Configuration best practice guidance needs to be reviewed periodically, vulnerability announcements monitored, and configuration standards updated.

1. Ensure proper deployment and configuration of encryption protocols, adhering to current best practices and standards.
2. Use valid and trusted certificates for encrypted communications to prevent man-in-the-middle attacks.
3. Prevent the possibility of downgrading encrypted connections to weaker or unencrypted states.
4. Regularly review and update the cryptographic setup to address new vulnerabilities and maintain strong security.

For detailed advice on how to mitigate threats related to the card, see the ASVS and OWASP Developer Guide requirements in the table below.