Another day, another tool 😉
Today I’m proudly releasing the first version of apnbf, a small python script designed for enumerating valid APNs (Access Point Name) on a GTP-C speaking device. It tries to establish a new PDP session with the endpoint via sending a createPDPContextRequest. This request needs to include a valid APN, so one can easily distinguish from a valid APN (which will be answered with a createPDPContextResponse) and an invalid APN (which will be answered with an error indication message). In addition the tool also parses the error indication and displays the reason (which should be “Missing or unknown APN” in case of an invalid APN).
Don’t waste time, get the source here (5a122f198ea35b1501bc3859fd7e87aa57ef853a)