Python : Key value as initialization vector

The application performs encryption with the initialization vector (IV), which coincides with the encryption key. In the case of encrypting the associated messages with the key and the value of IV coinciding with it, the attacker can receive information about the message. For secure encryption it is necessary that IV be cryptographically pseudo-random, that is unpredictable for the attacker.

Sensitive Data Exposure vulnerabilities take the third place in the “OWASP Top 10 2017” web-application vulnerabilities ranking.