name: A5/2
full_form: Encryption algorithm A5/2
context: This is the main threat to the 2G GBA solution. 1) An attacker (being in the possession of 2G GBA equipment) could try to perform a Man-in-the-middle-attack, impersonating a genuine GSM user to the BSF. In this scenario the attacker would be at the client end of the TLS tunnel to the BSF and send the challenge to the target GSM user, in order to obtain SRES and Kc. However, for the attack to be successful, he would have to find also Kc within the runtime allowed for steps 3 to 5 of the protocol over Ub, as specified in Annex I.5.2. This may be feasible when the terminal of the target GSM user still runs A5/2. A5/2 will be removed from networks by the end of 2006, and will not be present in any 2G GBA enabled terminals. A vulnerability caused by A5/2 would only exist in the case where a GSM user has subscribed to 2G GBA feature, but uses his SIM in an old terminal with A5/2 enabled while being targeted by the attacker. But the practical implications of this remaining vulnerability are
description: A5/2 is a cryptographic algorithm used in GSM (Global System for Mobile Communications) networks to encrypt communication between mobile devices and base stations. It aims to secure voice calls, text messages, and other data transmitted over the network.
explanation: A5/2 is explicitly described as an encryption algorithm within the context of GSM networks. Its purpose is to protect communication confidentiality, placing it firmly within the category of Encryption Algorithms.
section_title: L.1	Impersonation of the UE to the BSF during the run of the Ub protocol
biotag_Context: O,O,O,O,O,O,O,B-Technology,B-Technology,O,O,O,O,O,O,O,O,O,B-Technology,B-Technology,O,O,O,O,O,O,O,O,O,O,B-Network,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,B-Protocol,O,O,O,B-Network Function,O,O,O,O,O,O,O,B-Network,O,O,O,O,O,B-Parameter,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,B-Parameter,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,B-Network,O,O,O,O,B-Miscellaneous,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,B-Technology,B-Technology,O,O,O,O,O,O,B-Miscellaneous,O,O,O,O,O,O,O,O,B-Network,O,O,O,O,B-Technology,B-Technology,O,O,O,O,B-Device,O,O,O,O,O,B-Miscellaneous,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O
biotag_Description: B-Miscellaneous,O,O,O,O,O,O,B-Network,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O