Phlox com.phlox.simpleserver.plus (aka Simple HTTP Server PLUS) 1.8.1-plus has an Android manifest file that contains an entry with the android:allowBackup attribute set to true. This could be leveraged by an attacker with physical access to the device.
Phlox com.phlox.simpleserver (aka Simple HTTP Server) 1.8 and com.phlox.simpleserver.plus (aka Simple HTTP Server PLUS) 1.8.1-plus have a hardcoded aKySWb2jjrr4dzkYXczKRt7K (AES) encryption key. An attacker with physical access to the application's source code or binary can extract this key & use it decrypt the TLS secret.