I2P is an anonymizing network, offering a simple layer that identity-sensitive applications can use to securely communicate. All data is wrapped with several layers of encryption, and the network is both distributed and dynamic, with no trusted parties.
Not a bug. This is a the name of a property which is stored in a configuration file, format would be i2cp.leaseSetSecret=secret. It is not the value of the property, which is the actual secret.
line:70 Avoid hardcoding values that are meant to be secret. Found hardcoded secret.
core/java/src/net/i2p/client/impl/RequestLeaseSetMessageHandler.java#L70)