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Generate One Time Key Code

Perfect! Now that we have the key file we can work on a disarm capability. Several intelligence reports suggest that terrorists use a secure token (i.e., small hardware device) for generating unique one-time codes for authenticating to the IED when sending commands. We believe these codes change over time and are only valid for a certain time window and for specific device serial numbers. Based on previous signatures you provided, we have located the armed IED that is using the same version of software and key serial number from Task 3 and we need to disarm it ASAP. We do not have the secure token that corresponds to the device, but we still need to be able to authenticate to it with the correct code in order to disarm it. Your objective for this task is to figure out how to generate valid one-time codes and provide one that we can use to disarm the IED. The decrypted key file you provided earlier should help with this part.

captured client file: client
captured server file: server
captured library: captured key file: 952606818.key.enc

source: Codebreaker Challenge, 2016

solution: solution

Paul Erdos
Ladies on Campus
Oscar Robinson