Cyber Security in the Age of Large-Scale Adversaries

Aktuelle Forschungsmeldungen

Zuwendungen und Ehrungen

Mitglied der Leopoldina (2019, Christof Paar)

Program Co-Chair of the IEEE S&P (2021/22, Thorsten Holz)

ERC Advanced Grant  (2015, Christof Paar)

ERC Starting Grant (2014,Thorsten Holz)

ERC Consolidator Grant (2013, Eike Kiltz)

DFG Gottfried Wilhelm Leibniz Preis (2008, Holger Boche)

DFG Heisenberg Professorship (2015, Gregor Leander)

DFG Heinz Maier-Leibnitz Preis (2011, Thorsten Holz)

DFG Emmy-Noether Program (2008, Aydin Sezgin)

NWO Vici Grant (The Netherlands) (2012, Dan Bernstein)

Alexander v. Humboldt-Foundation Sofja Kovalevskaja Award (2010, Eike Kiltz)

13 Best Paper Awards bei führenden Kryptografie- & Sicherheits-Konferenzen (diverse)

ACM SIGSAC Doctoral Dissertation Award (2016, Lucas Davi)

DHL Innovation Award (2013, Gregor Leander, Christof Paar)

IBM Faculty Award (2013, Angela Sasse)

NRW Innovationspreis (2012, Christof Paar)

Facebook Internet Defense Prize at USENIX Security (2014, Thorsten Holz)

German IT-Security Award (1.Platz) (2010, Gregor Leander, Christof Paar)

German IT-Security Award (2.Platz) (2012, Eike Kiltz)

VDE Johann-Philipp-Reis Prize (2007, Holger Boche)

Fellow of the Royal Academy of Engineering (2015, Angela Sasse)

Fellow of the Institute of Mathematical Statistics (2013, Holger Dette)

IEEE Fellow (2010, Christof Paar)

IEEE Fellow (2011, Holger Boche)

IACR Fellow (2017, Christof Paar)

Young Fellow of NRW Academy of Sciences, Humanities & Arts (2015, Tim Güneysu)

Herausragende Publikationen


Au­ro­ra: Sta­tis­ti­cal Crash Ana­ly­sis for Au­to­ma­ted Root Cause Ex­pla­na­ti­on

Tim Bla­zyt­ko, Mo­ritz Schlö­gel, Cor­ne­li­us Ascher­mann, Ali Ab­ba­si, Joel Frank, Simon Wör­ner, Thors­ten Holz

USE­NIX Se­cu­ri­ty Sym­po­si­um, Bos­ton, MA, USA, Au­gust 2020

(...) In this paper, we propose an automated analysis approach that does not only identify the root cause of a given crashing input for a binary executable, but also provides the analyst with context information on the erroneous behavior that characterizes crashing inputs. (...)


Everybody’s a Target: Scalability in Public-Key Encryption

Benedikt Auerbach, Federico Giacon, and Eike Kiltz.

39th Annual International Conference on the Theory and Applications of Cryptographic, 2020

For 1≤m≤n, we consider a natural m-out-of-n multi-instance scenario for a public-key encryption (PKE) scheme. An adversary, given n independent instances of PKE, wins if he breaks at least m out of the n instances. In this work, we are interested in the scaling factor of PKE schemes, SF, which measures how well the difficulty of breaking m out of the n instances scales in m. (...)


Eth­B­MC: A Boun­ded Model Che­cker for Smart Contracts

Joel Frank, Cor­ne­li­us Ascher­mann, Thors­ten Holz

USE­NIX Se­cu­ri­ty Sym­po­si­um, Bos­ton, MA, USA, Au­gust 2020

We surveyed eight recently proposed static analyzers for Ethereum smart contracts and found that none of them captures all relevant features of the Ethereum ecosystem. For example, we discovered that a precise memory model is missing and inter-contract analysis is only partially supported. Based on these insights, we present the design and implementation of ETHBMC. (...)


IJON: Ex­plo­ring Deep State Spaces via Fuz­zing

Cor­ne­li­us Ascher­mann, Ser­gej Schu­mi­lo, Ali Ab­ba­si, Thors­ten Holz

IEEE Sym­po­si­um on Se­cu­ri­ty and Pri­va­cy ("Oak­land"), San Jose, CA, May 2020

In this paper, we propose IJON, an annotation mechanism that a human analyst can use to guide the fuzzer. In contrast to the two aforementioned techniques, this approach allows a more systematic exploration of the program’s behavior based on the data representing the internal state of the program. As a consequence, using only a small (usually one line) annotation, a user can help the fuzzer to solve previously unsolvable challenges. (...)


Misleading Authorship Attribution of Source Code using Adversarial Learning

Erwin Quiring, Alwin Maier, and Konrad Rieck, TU Braunschweig

29th USENIX Security Symposium, 2019

In this paper, we present a novel attack against authorship attribution of source code. We exploit that recent attribution methods rest on machine learning and thus can be deceived by adversarial examples of source code. Our attack performs a series of semantics-preserving code transformations that mislead learning-based attribution but appear plausible to a developer. (...)


The SPHINCS+ Signature Framework

Daniel J. Bernstein and Andreas Hülsing and Stefan Kölbl and Ruben Niederhagen and Joost Rijneveld and Peter Schwabe

ACM SIGSAC Conference on Computer and Communications Security 2019

We introduce SPHINCS+, a stateless hash-based signature framework. SPHINCS+ has significant advantages over the state of the art in terms of speed, signature size, and security, and is among the nine remaining signature schemes in the second round of the NIST PQC standardization project. One of our main contributions in this context is a new few-time signature scheme that we call FORS. (...)


This PIN Can Be Ea­si­ly Gues­sed: Ana­ly­zing the Se­cu­ri­ty of Smart­pho­ne Un­lock PINs

Phil­ipp Mar­kert, Da­ni­el V. Bai­ley, Ma­xi­mi­li­an Golla, Mar­kus Dür­muth, Adam J. Aviv

IEEE Sym­po­si­um on Se­cu­ri­ty and Pri­va­cy (SP '20). San Fran­cis­co, Ca­li­for­nia, May, 2020

In this paper, we provide the first comprehensive study of user-chosen 4- and 6-digit PINs (n=1220) collected on smartphones with participants being explicitly primed for device unlocking. We find that against a throttled attacker (with 10, 30, or 100 guesses, matching the smartphone unlock setting), using 6-digit PINs instead of 4-digit PINs provides little to no increase in security, and surprisingly may even decrease security.


Hy­per-Cu­be: High-Di­men­sio­nal Hy­per­vi­sor Fuz­zing

Ser­gej Schu­mi­lo, Cor­ne­li­us Ascher­mann, Ali Ab­ba­si, Simon Wör­ner, Thors­ten Holz

Net­work and Di­stri­bu­ted Sys­tem Se­cu­ri­ty Sym­po­si­um (NDSS), San Diego, Ca­li­for­nia, USA, Fe­bru­ary 2020

In this paper, we present the design and implementation of HYPER-CUBE, a novel fuzzer that aims explicitly at testing hypervisors in an efficient, effective, and precise way. Our approach is based on a custom operating system that implements a custom bytecode interpreter. This high-throughput design for long-running, interactive targets allows us to fuzz a large number of both open source and proprietary hypervisors.


McTiny: fast high-confidence post-quantum key erasure for tiny network servers

Daniel J. Bernstein and Tanja Lange

29th USENIX Security Symposium, 2019

This paper describes a protocol, suitable for today's networks and tiny servers, in which clients transmit their code-based one-time public keys to servers. Servers never store full client public keys but work on parts provided by the clients, without having to maintain any per-client state. Intermediate results are stored on the client side in the form of encrypted cookies and are eventually combined by the server to obtain the ciphertext. (...)


IM­P4GT: IM­Per­so­na­ti­on At­tacks in 4G NeT­works

David Rupp­recht, Ka­tha­ri­na Kohls, Thors­ten Holz, Chris­ti­na Pöp­per

Net­work and Di­stri­bu­ted Sys­tem Se­cu­ri­ty Sym­po­si­um (NDSS), San Diego, Ca­li­for­nia, USA, Fe­bru­ary 2020

In this work, we introduce a novel cross-layer attack that exploits the existing vulnerability on layer two and extends it with an attack mechanism on layer three. More precisely, we take advantage of the default IP stack behavior of operating systems and show that combining it with the layer-two vulnerability allows an active attacker to impersonate a user towards the network and vice versa; we name these attacks IMP4GT. (...)


1 Trillion Dollar refund - how to spoof PDF signatures

Vla­dis­lav Mla­de­nov, Chris­ti­an Main­ka, Kars­ten Meyer zu Sel­hau­sen, Mar­tin Gro­the, Jörg Schwenk

26th ACM Con­fe­rence on Com­pu­ter and Com­mu­ni­ca­ti­ons Se­cu­ri­ty, 2019

In this paper, we present the first comprehensive security evaluation on digital signatures in PDFs. We introduce three novel attack classes which bypass the cryptographic protection of digitally signed PDF files allowing an attacker to spoof the content of a signed PDF. We analyzed 22 different PDF viewers and found 21 of them to be vulnerable. (...)


GRI­MOIRE: Syn­the­si­zing Struc­tu­re while Fuz­zing

2019 - Tim Bla­zyt­ko, Cor­ne­li­us Ascher­mann, Mo­ritz Schlö­gel, Ali Ab­ba­si, Ser­gej Schu­mi­lo, Simon Wör­ner, Thors­ten Holz

USE­NIX Se­cu­ri­ty Sym­po­si­um, Santa Clara, CA, USA, Au­gust 2019

In this paper, we present the design and implementation of GRIMOIRE, a fully automated coverage-guided fuzzer which works without any form of human interaction or pre-configuration; yet, it is still able to efficiently test programs that expect highly structured inputs. (...)


“John­ny, you are fired!” – Spoo­fing Open­PGP and S/MIME Si­gna­tu­res in Emails

2019 - Jens Mül­ler, Mar­cus Brink­mann, Da­mi­an Pod­debni­ak, Hanno Böck, Se­bas­ti­an Schin­zel, Juraj So­mo­rovs­ky, Jörg Schwenk

28th USE­NIX Se­cu­ri­ty Sym­po­si­um (USE­NIX Se­cu­ri­ty '19)

In this work we show practical forgery attacks against various implementations of OpenPGP and S/MIME email signature verification in five attack classes: (1) We analyze edge cases in S/MIME’s container format. (2) We exploit in-band signaling in the GnuPG API, the most widely used OpenPGP implementation. (3) We apply MIME wrapping attacks that abuse the email clients’ handling of partially signed messages. (...)


On the Security of Two-Round Multi-Signatures

Manu Drijvers, Kasra Edalatnejad, Bryan Ford, Eike Kiltz, Julian Loss, Gregory Neven and Igors Stepanovs

In 40th IEEE Symposium on Security and Privacy: May 20 2019 to May 22 2019  San Fransisco, CA, US; 2019; pp 780–797.

In this work, we point out serious security issues in all currently known two-round multi-signature schemes (without pairings). First, we prove that none of the schemes can be proved secure without radically departing from currently known techniques. Namely, we show that if the one-more discrete-logarithm problem is hard, then no algebraic reduction exists that proves any of these schemes secure under the discrete-logarithm or one-more discrete-logarithm problem. (...)


Glitch-Resistant Masking Revisite

Thorben Moos, Amir Moradi, Tobias Schneider, François-Xavier Standaert.

IACR Transactions on Cryptographic Hardware and Embedded Systems, 2019(2), 256-292. Best Paper Award.

(...) In this paper, we argue that the lack of proofs for TIs, DOM, UMA and GLM makes the interpretation of their security guarantees difficult as the number of shares increases. For this purpose, we first put forward that the higher-order variants of all these schemes are affected by (local or composability) security flaws in the (robust) probing model, due to insufficient refreshing. (…)


Adversarial Attacks Against Automatic Speech Recognition Systems via Psychoacoustic Hiding.

Lea Schönherr, Katharina Kohls, Steffen Zeiler, Thorsten Holz, Dorothea Kolossa

NDSS ISOC Network and Distributed System Security Symposium 2019.

(...) In this paper, we introduce a new type of adversarial examples based on psychoacoustic hiding. Our attack exploits the characteristics of DNN-based ASR systems, where we extend the original analysis procedure by an additional backpropagation step. (...)


AntiFuzz: Impeding Fuzzing Audits of Binary Executables.

Emre Güler, Cornelius Aschermann, Ali Abbasi, Thorsten Holz.

USENIX Security Symposium: conference proceedings ; Santa Clara, CA, USA, August 14-16, 2019; pp 1931–1948.

In this paper, we introduce several techniques to protect a binary executable against an analysis with automated bug finding approaches that are based on fuzzing, symbolic/concolic execution, and taint-assisted fuzzing (commonly known as hybrid fuzzing). More specifically, we perform a systematic analysis of the fundamental assumptions of bug finding tools and develop general countermeasures for each assumption.



ERC Advanced Grant 20162021 Paar

ERC Consolidator Grant 20142019 Kiltz

ERC Starting Grant 20152020 Holz

NWO Vici Grant 20122017 Bernstein

AvH Sofja Kovalevskaja Award 20102015 Kiltz

DFG Heisenberg Professorship 20152018 Leander

DFG Research Training Group “Cryptography for Ubiquitous Computing" 2012 – 2017 May (co-spokesperson), Paar (cospokesperson),Dürmuth, Güneysu, Holz, Kiltz, Kolossa, Leander, Schwenk

NRW Doctoral Training Group “Security for Humans in Cyberspace” 20162019 Paar (spokesperson), Dürmuth, Holz, Kiltz, Kolossa, May, Rummel

NRW Doctoral Training Group “Human-Centered Systems Security“ 2017 2020 Holz (co-spokesperson), Schwenk (cospokesperson), Dürmuth

Projects in DFG SFB “Statistical modeling of nonlinear dynamic processes” 20132021 Dette (deputy spokesperson)

GCHQ/EPSRC project “UK Research Institute in Science of Cyber Security (RISCS)” 20102021 Sasse (director)

EU project “Post-quantum cryptography for longterm security” 2015 – 2018 Bernstein (co-coordinator), Lange (co-coordinator), Güneysu, Paar

EU project “FutureTrust” 20162019 Schwenk (coordinator)

EU European Training Network “ECRYPT-NET” 20152018 Bernstein, Güneysu, Kiltz, Lange, May, Paar

BMWi project “Secure eMobility” 2012 – 2014 Güneysu, Holz, Paar, Schwenk


Geben Sie Ihren Benutzernamen und Ihr Passwort ein, um sich an der Website anzumelden