Even if you find a working keygen that produces a valid checksum, the activation server will reject it because the license block list is still active. Kaspersky’s servers remember every leaked key from 2013. They return a specific error: "Activation code is blocked for this application version."
The "Internet Security" line has largely been replaced by the newer subscription-based Kaspersky Standard, Plus, and Premium plans. How Kaspersky Activation Keys Work keys for kaspersky internet security 2013