Security

SigOver + alpha

Signal overshadowing attack on LTE and its applications
As Long-Term Evolution (LTE) communication is based on over-the-air signaling, a legitimate signal can potentially be counterfeited by a malicious signal. Although most LTE signaling messages are protected from modification using cryptographic primitives, broadcast messages and some of the unicast messages are unprotected. In this talk, we would like to introduce a signal injection attack that exploits the fundamental weakness of unprotected messages in LTE and modifies a transmitted signal over the air. This attack, which is referred to as signal overshadowing (named SigOver) overwrites a portion of the legitimate signal to inject manipulated signal into the victim while the victim is connected to a legitimate cellular network. In most aspects, SigOver attack is superior to FBS (Fake Bas Station) and MitM (Man-in-the-Middle) attack, in terms of Efficiency, Effectiveness, and Stealthiness. Thus, Sigover results in new attacks exploiting broadcast channel and unicast channel. For example, SigOver attack on the broadcast messages can affect a large number of nearby UEs simultaneously such as signaling storm, Denial-Of-Service, downgrading attack, location tracking, and fake emergency alert. SigOver attack on unicast channel can silently hand over victims to FBS and perform MitM attack. Sigover attack is currently zero-day. Since it exploits the fundamental problems in LTE physical signal, it will remain effective until 3GPP standards change.
In detail, we talk about the implementation of the SigOver, the first practical realization of the signal overshadowing attack on the LTE broadcast signals, using a low-cost Software Defined Radio (SDR) platform and open-source LTE library. The SigOver attack was tested against 10 smartphones connected to a real-world network, and all were successful. The experimental result shows that the SigOver overshadows the target signal and causes the victim device to decode it with 98% success rate with only 3 dB power difference from a legitimate signal. On the other hand, attacks utilizing an FBS have only 80% success rate even with 35 dB power difference. This implies that the SigOver can inconspicuously inject any LTE message and hand over victims to FBS for the Man-in-the-Middle attack. Presentation Snapshot : 1. Overview on LTE Architecture including structure, security aspects, and types of messages. Broadcast messages and some of the unicast messages are unprotected; thus they have a fundamental weakness. 2. Introduction of SigOver Attack, attack vectors, detailed implementational design, and issues on performing the attack. SigOver attack can manipulate unprotected LTE signals. 3. Comparison with FBS (Fake Base Station) Attacker and MitM (Man-in-the-Middle) Attacker, in terms of Efficiency, Effectiveness, and Stealthiness. In most aspects, SigOver is superior than FBS and MitM attacker. 4. Possible exploitations of broadcast channel using SigOver Attacks, such as signaling storm, Denial-Of-Service, downgrading attack, location tracking, and fake emergency alert. 5. Possible exploitations of unicast channel using SigOver Attacks. An attacker can manipulate every individual unprotected downlink messages. As the whole injection process is silent, this results in whole new types of attacks. 6. For example, an attacker can silently hand over victims to the fake base station. Once the victim is connected to the FBS, attacks including Man-in-the-Middle attack are possible.

Additional information

Type lecture
Language English

More sessions

12/27/19
Security
Borg
Nowadays, Windows is still the most popular OS used in the world. It's very important for red teams / attackers to maintain the authority after they get into the OS by penetration test. So they need a vulnerability to hide in windows to escalate their account to system privilege.
12/27/19
Security
Hannes Mehnert
Dijkstra
Is the way we run services these days sustainable? The trusted computing base -- the lines of code where, if a flaw is discovered, jeopardizes the security and integrity of the entire service -- is enormous. Using orchestration systems that contain millions of lines of code, and that execute shell code, does not decrease this. This talk will present an alternative, minimalist approach to secure network services - relying on OCaml, a programming language that guarantees memory safety - composing ...
12/27/19
Security
littlelailo
Eliza
This talk is about running unsigned code at boot on iOS 11. I will demonstrate how you can start out with a daemon config file and end up with kernel code execution.
12/27/19
Security
Will Scott
Ada
It is easier to chat online securely today than it ever has been. Widespread adoption of signal, wire, and the private mode of WhatsApp have led a broader recognition of the importance of end-to-end encryption. There's still plenty of work to be done in finding new designs that balance privacy and usability in online communication.
12/27/19
Security
nba::yoh
Dijkstra
The 3DS is reaching end of life but has not revealed all its weaknesses yet. This talk will go through the process of reverse engineering an undocumented communication protocol and show how assessing hard-to-reach features yields dangerous results, including remote code execution exploits!
12/27/19
Security
Samuel Groß
Ada
So called “0-click” exploits, in which no user interaction is required to compromise a mobile device, have become a highly interesting topic for security researchers, and not just because Apple announced a one million dollar bug bounty for such exploits against the iPhone this year. This talk will go into the details of how a single memory corruption vulnerability in iMessage was remotely exploited to compromise an iPhone. The insights gained from the exploitation process will hopefully help ...
12/27/19
Security
Ada
Herzstück der digitalen Gesundheitsversorgung für 73 Millionen Versicherte ist die hochsichere, kritische Telematik-Infrastruktur mit bereits 115.000 angeschlossenen Arztpraxen. Nur berechtigte Teilnehmer haben über dieses geschlossene Netz Zugang zu unseren medizinischen Daten. Ein "Höchstmaß an Schutz" also, wie es das Gesundheitsministerium behauptet? Bewaffnet mit 10.000 Seiten Spezifikation und einem Faxgerät lassen wir Illusionen platzen und stellen fest: Technik allein ist auch ...