Information Security Commons^™

Who Should Pay The Cost: A Game-Theoretic Model For Government Subsidized Investments To Improve National Cybersecurity, Xinrun Wang, Bo An, Hau Chan

Research Collection School Of Computing and Information Systems

Due to the recent cyber attacks, cybersecurity is becoming more critical in modern society. A single attack (e.g., WannaCry ransomware attack) can cause as much as $4 billion in damage. However, the cybersecurity investment by companies is far from satisfactory. Therefore, governments (e.g., in the UK) launch grants and subsidies to help companies to boost their cybersecurity to create a safer national cyber environment. The allocation problem is hard due to limited subsidies and the interdependence between self-interested companies and the presence of a strategic cyber attacker. To tackle the government's allocation problem, we introduce a Stackelberg game-theoretic model where …

Control-Flow Carrying Code, Yan Lin, Debin Gao

Research Collection School Of Computing and Information Systems

Control-Flow Integrity (CFI) is an effective approach in mitigating control-flow hijacking attacks including code-reuse attacks. Most conventional CFI techniques use memory page protection mechanism, Data Execution Prevention (DEP), as an underlying basis. For instance, CFI defenses use read-only address tables to avoid metadata corruption. However, this assumption has shown to be invalid with advanced attacking techniques, such as Data-Oriented Programming, data race, and Rowhammer attacks. In addition, there are scenarios in which DEP is unavailable, e.g., bare-metal systems and applications with dynamically generated code. We present the design and implementation of Control-Flow Carrying Code (C3), a new CFI enforcement without …

Dynopvm: Vm-Based Software Obfuscation With Dynamic Opcode Mapping, Xiaoyang Cheng, Yan Lin, Debin Gao

Research Collection School Of Computing and Information Systems

VM-based software obfuscation has emerged as an effective technique for program obfuscation. Despite various attempts in improving its effectiveness and security, existing VM-based software obfuscators use potentially multiple but static secret mappings between virtual and native opcodes to hide the underlying instructions. In this paper, we present an attack using frequency analysis to effectively recover the secret mapping to compromise the protection, and then propose a novel VM-based obfuscator in which each basic block uses a dynamic and control-flow-aware mapping between the virtual and native instructions. We show that our proposed VM-based obfuscator not only renders the frequency analysis attack …

Towards Understanding Android System Vulnerabilities: Techniques And Insights, Daoyuan Wu, Debin Gao, Eric K. T. Cheng, Yichen Cao, Jintao Jiang, Robert H. Deng

Research Collection School Of Computing and Information Systems

As a common platform for pervasive devices, Android has been targeted by numerous attacks that exploit vulnerabilities in its apps and the operating system. Compared to app vulnerabilities, systemlevel vulnerabilities in Android, however, were much less explored in the literature. In this paper, we perform the first systematic study of Android system vulnerabilities by comprehensively analyzing all 2,179 vulnerabilities on the Android Security Bulletin program over about three years since its initiation in August 2015. To this end, we propose an automatic analysis framework, upon a hierarchical database structure, to crawl, parse, clean, and analyze vulnerability reports and their publicly …

A Closer Look Tells More: A Facial Distortion Based Liveness Detection For Face Authentication, Yan Li, Zilong Wang, Yingjiu Li, Robert H. Deng, Binbin Chen, Weizhi Meng, Hui Li

Research Collection School Of Computing and Information Systems

Face authentication is vulnerable to media-based virtual face forgery (MVFF) where adversaries display photos/videos or 3D virtual face models of victims to spoof face authentication systems. In this paper, we propose a liveness detection mechanism, called FaceCloseup, to protect the face authentication on mobile devices. FaceCloseup detects MVFF-based attacks by analyzing the distortion of face regions in a user's closeup facial videos captured by built-in camera on mobile device. It can detect MVFF-based attacks with an accuracy of 99.48%.

Splitsecond: Flexible Privilege Separation Of Android Apps, Jehyun Lee, Akshaya Venkateswara Venkateswara Raja, Debin Gao

Research Collection School Of Computing and Information Systems

Android applications have been attractive targets to attackers due to the large number of users and the sensitive information they possess. After the success of the first step of an attack exploiting a software vulnerability, the consequential damage is primarily determined by the criticality and the amount of Android permissions that a victim application has. As a countermeasure, process separation techniques that isolate potentially vulnerable components — usually native libraries — from the critical data and permissions, have been proposed. However, existing techniques offer little flexibility in the separation, e.g., with all native code being placed into one process without …

Securing Messaging Services Through Efficient Signcryption With Designated Equality Test, Yujue Wang, Hwee Hwa Pang, Robert H. Deng, Yong Ding, Qianhong Wu, Bo Qin

Research Collection School Of Computing and Information Systems

To address security and privacy issues in messaging services, we present a public key signcryption scheme with designated equality test on ciphertexts (PKS-DET) in this paper. The scheme enables a sender to simultaneously encrypt and sign (signcrypt) messages, and to designate a tester to perform equality test on ciphertexts, i.e., to determine whether two ciphertexts signcrypt the same underlying plaintext message. We introduce the PKS-DET framework, present a concrete construction and formally prove its security against three types of adversaries, representing two security requirements on message confidentiality against outsiders and the designated tester, respectively, and a requirement on message unforgeability …

Oblidc: An Sgx-Based Oblivious Distributed Computing Framework With Formal Proof, Pengfei Wu, Qingni Shen, Robert H. Deng, Ximeng Liu, Yinghui Zhang, Zhonghai Wu

Research Collection School Of Computing and Information Systems

Data privacy is becoming one of the most critical concerns in cloud computing. Several proposals based on Intel SGX such as VC3 and M2R have been introduced in the literature to protect data privacy during job execution in the cloud. However, a comprehensive formal proof of their security guarantees is still lacking. In this paper, we propose ObliDC, a general UC-secure SGX-based oblivious distributed computing framework. First, we model the life-cycle of a distributed computing job as data-flow graphs. Under the assumption of malicious, adaptive adversaries in the cloud, we then formally define data privacy of a distributed computing job …

Pruneable Sharding-Based Blockchain Protocol, Xiaoqin Feng, Jianfeng Ma, Yinbin Miao, Qian Meng, Ximeng Liu, Qi Jiang, Hui Li

Research Collection School Of Computing and Information Systems

As a distributed ledger technology, the block-chain has gained much attention from both the industrical and academical fields, but most of the existing blockchain protocols still have the cubical dilatation problem. Although the latest Rollerchain has mitigated this issue by changing the blockheader's contents, the low efficiency, severe capacity expansion and non-scalability problems still hinder the adoption of Rollerchain in practice. To this end, we present the pruneable sharding-based blockchain protocol by utilizing the sharding technique and PBFT(Practical Byzantine Fault Tolerance) algorithm in the improved Rollerchain, which has high efficiency, slow cubical dilatation, small capacity expansion and high scalability. Moreover, …

The Wiener Attack On Rsa Revisited: A Quest For The Exact Bound, Willy Susilo, Joseph Tonien, Guomin Yang

Research Collection School Of Computing and Information Systems

Since Wiener pointed out that the RSA can be broken if the private exponent d is relatively small compared to the modulus N (using the continued fraction technique), it has been a general belief that the Wiener attack works for. On the contrary, in this work, we give an example where the Wiener attack fails with, thus, showing that the bound is not accurate as it has been thought of. By using the classical Legendre Theorem on continued fractions, in 1999 Boneh provided the first rigorous proof which showed that the Wiener attack works for. However, the question remains whether …

The Chilling Effect Of Enforcement Of Computer Misuse: Evidences From Online Hacker Forums, Qiu-Hong Wang, Rui-Bin Geng, Seung Hyun Kim

Research Collection School Of Computing and Information Systems

To reduce the availability of hacking tools for violators in committing cybersecurity offences, many countries have enacted the legislation to criminalize the production, distribution and possession of computer misuse tools with offensive intent. However, the dual-use nature of cybersecurity technology increases the difficulty in the legal process to recognize computer misuse tools and predict their harmful outcome, which leads to unintended impacts of the enforcement on the provision of techniques valuable for information security defence. Leveraging an external shock in online hacker forums, this study examines the potential impacts of the enforcement of computer misuse on users' contribution to information …

A Scalable Approach To Joint Cyber Insurance And Security-As-A-Service Provisioning In Cloud Computing, Jonathan David Chase, Dusit Niyato, Ping Wang, Sivadon Chaisiri, Ryan K. L. Ko

Research Collection School Of Computing and Information Systems

As computing services are increasingly cloud-based, corporations are investing in cloud-based security measures. The Security-as-a-Service (SECaaS) paradigm allows customers to outsource security to the cloud, through the payment of a subscription fee. However, no security system is bulletproof, and even one successful attack can result in the loss of data and revenue worth millions of dollars. To guard against this eventuality, customers may also purchase cyber insurance to receive recompense in the case of loss. To achieve cost effectiveness, it is necessary to balance provisioning of security and insurance, even when future costs and risks are uncertain. To this end, …

Location Based Encryption, Tran Viet Xuan Phuong, Willy Susilo, Guomin Yang, Jun Yan, Dongxi Liu

Research Collection School Of Computing and Information Systems

We first propose a 2D Location Based Encryption (LBE) scheme, where the setting includes a geography center system and the 2D triangle area including the set of locations. A user joining in the system is provided with a pre-arranged key, which belongs to her/his location. If the user’s location is belonging to this area, he/she can decrypt the message. Our proposed scheme achieves a constant ciphertext size in encryption algorithm and decryption cost. Beyond the 2D-LBE scheme, we explore the 3D-LBE scheme; whereby the location is set up in the 3D dimensions. This proposed scheme is an extension of 2D-LBE …

Decentralise Me, Paul Robert Griffin

MITB Thought Leadership Series

If you are in need of a reminder of the levels of hype surrounding blockchain, then look no further than Japan’s J-Pop sensation Kasotsuka Shojo, otherwise known as the Virtual Currency Girls who, with their debut track “The Moon and Cryptocurrencies and Me”, aim to educate fans about cryptocurrencies in an entertaining way.

Collusion Attacks And Fair Time-Locked Deposits For Fast-Payment Transactions In Bitcoin, Xingjie Yu, Shiwen Michael Thang, Yingjiu Li, Robert H. Deng

Research Collection School Of Computing and Information Systems

In Bitcoin network, the distributed storage of multiple copies of the block chain opens up possibilities for doublespending, i.e., a payer issues two separate transactions to two different payees transferring the same coins. While Bitcoin has inherent security mechanism to prevent double-spending attacks, it requires a certain amount of time to detect the doublespending attacks after the transaction has been initiated. Therefore, it is impractical to protect the payees from suffering in double-spending attacks in fast payment scenarios where the time between the exchange of currency and goods or services is shorten to few seconds. Although we cannot prevent double-spending …

Crowdbc: A Blockchain-Based Decentralized Framework For Crowdsourcing, Ming Li, Jian Weng, Anjia Yang, Wei Lu, Yue Zhang, Lin Hou, Jiannan Liu, Yang Xiang, Robert H. Deng

Research Collection School Of Computing and Information Systems

Crowdsourcing systems which utilize the human intelligence to solve complex tasks have gained considerable interest and adoption in recent years. However, the majority of existing crowdsourcing systems rely on central servers, which are subject to the weaknesses of traditional trust-based model, such as single point of failure. They are also vulnerable to distributed denial of service (DDoS) and Sybil attacks due to malicious users involvement. In addition, high service fees from the crowdsourcing platform may hinder the development of crowdsourcing. How to address these potential issues has both research and substantial value. In this paper, we conceptualize a blockchain-based decentralized …

Key-Insulated And Privacy-Preserving Signature Scheme With Publicly Derived Public Key, Zhen Liu, Guomin Yang, Duncan S. Wong, Khoa Nguyen, Huaxiong Wang

Research Collection School Of Computing and Information Systems

Since the introduction of Bitcoin in 2008, cryptocurrency has been undergoing a quick and explosive development. At the same time, privacy protection, one of the key merits of cryptocurrency, has attracted much attention by the community. A deterministic wallet algorithm and a stealth address algorithm have been widely adopted in the community, due to their virtues on functionality and privacy protection, which come from a key derivation mechanism that an arbitrary number of derived keys can be generated from a master key. However, these algorithms suffer a vulnerability. In particular, when a minor fault happens (say, one derived key is …

Lightweight Privacy-Preserving Ensemble Classification For Face Recognition, Zhuo Ma, Yang Liu, Ximeng Liu, Jianfeng Ma, Kui Ren

Research Collection School Of Computing and Information Systems

The development of machine learning technology and visual sensors is promoting the wider applications of face recognition into our daily life. However, if the face features in the servers are abused by the adversary, our privacy and wealth can be faced with great threat. Many security experts have pointed out that, by 3-D-printing technology, the adversary can utilize the leaked face feature data to masquerade others and break the E-bank accounts. Therefore, in this paper, we propose a lightweight privacy-preserving adaptive boosting (AdaBoost) classification framework for face recognition (POR) based on the additive secret sharing and edge computing. First, we …

Managing The Power And Pitfalls Of Data In Ai, Singapore Management University

Perspectives@SMU

Ethics and education are crucial in maintaining data privacy and augmenting human ability

“It’s difficult to imagine the power that you’re going to have when so many different sorts of data are available.” – Tim Berners-Lee, father of the Internet

“Before Google, and long before Facebook, Bezos had realised that the greatest value of an online company lay in the consumer data it collected.” – George Packer, author for the New Yorker

On-The-Fly Android Static Analysis With Applications In Vulnerability Discovery, Daoyuan Wu

Dissertations and Theses Collection (Open Access)

Static analysis is a common program analysis technique extensively used in the software security field. Widely-used static analysis tools for Android, e.g., Amandroid and FlowDroid, perform the whole-app analysis which is comprehensive yet at the cost of huge overheads. In this dissertation, we make a first attempt to explore a novel on-demand analysis that creatively leverages bytecode search to guide inter-procedural analysis on the fly or just in time, and develop such on-the-fly analysis into a tool, called BackDroid, for Android apps. We further explore how the core technique of on-the-fly static analysis in BackDroid can enable different vulnerability studies …

Designated-Server Identity-Based Authenticated Encryption With Keyword Search For Encrypted Emails, Hongbo Li, Qiong Huang, Jian Shen, Guomin Yang, Willy Susilo

Research Collection School Of Computing and Information Systems

In encrypted email system, how to search over encrypted cloud emails without decryption is an important and practical problem. Public key encryption with keyword search (PEKS) is an efficient solution to it. However, PEKS suffers from the complex key management problem in the public key infrastructure. Its variant in the identity-based setting addresses the drawback, however, almost all the schemes does not resist against offline keyword guessing attacks (KGA) by inside adversaries. In this work we introduce the notion of designated-server identity-based authenticated encryption with keyword search (dIBAEKS), in which the email sender authenticates the message while encrypting so that …

Pptds: A Privacy-Preserving Truth Discovery Scheme In Crowd Sensing Systems, Chuan Zhang, Liehuang Zhu, Chang Xu, Kashif Sharif, Ximeng Liu

Research Collection School Of Computing and Information Systems

Benefiting from the fast development of human-carried mobile devices, crowd sensing has become an emerging paradigm to sense and collect data. However, reliability of sensory data provided by participating users is still a major concern. To address this reliability challenge, truth discovery is an effective technology to improve data accuracy, and has garnered significant attention. Nevertheless, many of state of art works in truth discovery, either failed to address the protection of participants' privacy or incurred tremendous overhead on the user side. In this paper, we first propose a privacy-preserving truth discovery scheme, named PPTDS-I, which is implemented on two …

A Blockchain-Based Location Privacy-Preserving Crowdsensing System, Mengmeng Yang, Tianqing Zhu, Kaitai Liang, Wanlei Zhou, Robert H. Deng

Research Collection School Of Computing and Information Systems

With the support of portable electronic devices and crowdsensing, a new class of mobile applications based on the Internet of Things (IoT) application is emerging. Crowdsensing enables workers with mobile devices to travel to specified locations and collect data, then send it back to the requester for rewards. However, the majority of the existing crowdsensing systems are based on centralized servers, which are prone to a high chance of attack, intrusion, and manipulation. Further, during the process of transmitting information to and from the service server, the worker's location is usually exposed. This raises the potential risk of a privacy …

Bilateral Liability-Based Contracts In Information Security Outsourcing, Kai-Lung Hui, Ping Fan Ke, Yuxi Yao, Wei Thoo Yue

Research Collection School Of Computing and Information Systems

We study the efficiency of bilateral liability-based contracts in managed security services (MSSs). We model MSS as a collaborative service with the protection quality shaped by the contribution of both the service provider and the client. We adopt the negligence concept from the legal profession to design two novel contracts: threshold-based liability contract and variable liability contract. We find that they can achieve the first best outcome when postbreach effort verification is feasible. More importantly, they are more efficient than a multilateral contract when the MSS provider assumes limited liability. Our results show that bilateral liability-based contracts can work in …

Adversarial Sample Detection For Deep Neural Network Through Model Mutation Testing, Jingyi Wang, Guoliang Dong, Jun Sun, Xinyu Wang, Zhang Peixin

Research Collection School Of Computing and Information Systems

No abstract provided.

Fair And Dynamic Data Sharing Framework In Cloud-Assisted Internet Of Everything, Yinbin Miao, Ximeng Liu, Kim-Kwang Raymond Choo, Robert H. Deng, Hongjun Wu, Hongwei Li

Research Collection School Of Computing and Information Systems

Cloud-assisted Internet of Things (IoT) is increasingly prevalent in our society, for example in home and office environment; hence, it is also known as cloud-assisted Internet of Everything (IoE). While in such a setup, data can be easily shared and disseminated (e.g., between a device, such as Amazon Echo and the cloud, such as Amazon AWS), there are potential security considerations that need to be addressed. Thus, a number of security solutions have been proposed. For example, searchable encryption (SE) has been extensively studied due to its capability to facilitate searching of encrypted data. However, threat models in most existing …

Cinema: Efficient And Privacy-Preserving Online Medical Primary Diagnosis With Skyline Query, Jianfeng Hua, Hui Zhu, Fengwei Wang, Ximeng Liu, Rongxing Lu, Hao Li, Yeping Zhang

Research Collection School Of Computing and Information Systems

Online medical primary diagnosis system, which can provide convenient medical decision support through applying mobile communication and data analysis technology, has been considered as a promising approach to improve the quality of healthcare service. However, it still faces many severe challenges on the privacy of users' health information and the accuracy of diagnosis result, which deter the wide adoption of online medical primary diagnosis system. In this paper, we propose an efficient and privacy-preserving online medical primary diagnosis (CINEMA) framework. Within CINEMA framework, users can access online medical primary diagnosing service accurately without divulging their medical data. Specifically, based on …

Peeling Back The (Onion) Layers Of The Dark Web, Singapore Management University

Perspectives@SMU

Manoeuvring the minefield of risk and exposure

Suaa: A Secure User Authentication Scheme With Anonymity For The Single & Multi-Server Environments, Nassoro M. R. Lwamo, Liehuang Zhu, Chang Xu, Kashif Sharif, Ximeng Liu, Chuan Zhang

Research Collection School Of Computing and Information Systems

The rapid increase in user base and technological penetration has enabled the use of a wide range of devices and applications. The services are rendered to these devices from single-server or highly distributed server environments, irrespective of their location. As the information exchanged between servers and clients is private, numerous forms of attacks can be launched to compromise it. To ensure the security, privacy, and availability of the services, different authentication schemes have been proposed for both single-server and multi-server environments. The primary performance objective of such schemes is to prevent most (if not all) attacks, with minimal computational costs …

See No Evil, Hear No Evil? Dissecting The Impact Of Online Hacker Forums, Wei T. Yue, Qiu-Hong Wang, Kai‐Lung Hui

Research Collection School Of Computing and Information Systems

Online hacker forums offer a prominent avenue for sharing hacking knowledge. Using a field dataset culled from multiple sources, we find that online discussion of distributed denial of service (DDOS) attacks in hackforums.net decreases the number of DDOS-attack victims. A 1% increase in discussion decreases DDOS attacks by 0.032% to 0.122%. This means that two DDOS-attack posts per day could reduce the number of victims by 700 to 2,600 per day. We find that discussion topics with similar keywords can variously increase or decrease DDOS attacks, meaning we cannot ascertain the impact of the discussion just by the post nature. …