Biblio

Found 377 results

Filters: First Letter Of Title is O  [Clear All Filters]
2019-06-10
Farooq, H. M., Otaibi, N. M..  2018.  Optimal Machine Learning Algorithms for Cyber Threat Detection. 2018 UKSim-AMSS 20th International Conference on Computer Modelling and Simulation (UKSim). :32-37.

With the exponential hike in cyber threats, organizations are now striving for better data mining techniques in order to analyze security logs received from their IT infrastructures to ensure effective and automated cyber threat detection. Machine Learning (ML) based analytics for security machine data is the next emerging trend in cyber security, aimed at mining security data to uncover advanced targeted cyber threats actors and minimizing the operational overheads of maintaining static correlation rules. However, selection of optimal machine learning algorithm for security log analytics still remains an impeding factor against the success of data science in cyber security due to the risk of large number of false-positive detections, especially in the case of large-scale or global Security Operations Center (SOC) environments. This fact brings a dire need for an efficient machine learning based cyber threat detection model, capable of minimizing the false detection rates. In this paper, we are proposing optimal machine learning algorithms with their implementation framework based on analytical and empirical evaluations of gathered results, while using various prediction, classification and forecasting algorithms.

2019-06-24
You, Y., Li, Z., Oechtering, T. J..  2018.  Optimal Privacy-Enhancing And Cost-Efficient Energy Management Strategies For Smart Grid Consumers. 2018 IEEE Statistical Signal Processing Workshop (SSP). :826–830.

The design of optimal energy management strategies that trade-off consumers' privacy and expected energy cost by using an energy storage is studied. The Kullback-Leibler divergence rate is used to assess the privacy risk of the unauthorized testing on consumers' behavior. We further show how this design problem can be formulated as a belief state Markov decision process problem so that standard tools of the Markov decision process framework can be utilized, and the optimal solution can be obtained by using Bellman dynamic programming. Finally, we illustrate the privacy-enhancement and cost-saving by numerical examples.

2019-03-06
Li, W., Li, S., Zhang, X., Pan, Q..  2018.  Optimization Algorithm Research of Logistics Distribution Path Based on the Deep Belief Network. 2018 17th International Symposium on Distributed Computing and Applications for Business Engineering and Science (DCABES). :60-63.

Aiming at the phenomenon that the urban traffic is complex at present, the optimization algorithm of the traditional logistic distribution path isn't sensitive to the change of road condition without strong application in the actual logistics distribution, the optimization algorithm research of logistics distribution path based on the deep belief network is raised. Firstly, build the traffic forecast model based on the deep belief network, complete the model training and conduct the verification by learning lots of traffic data. On such basis, combine the predicated road condition with the traffic network to build the time-share traffic network, amend the access set and the pheromone variable of ant algorithm in accordance with the time-share traffic network, and raise the optimization algorithm of logistics distribution path based on the traffic forecasting. Finally, verify the superiority and application value of the algorithm in the actual distribution through the optimization algorithm contrast test with other logistics distribution paths.

2019-08-26
Bhusari, A. A., Jawandhiya, P. M., Thakare, V. M..  2018.  Optimizing Performance of Anonymity Based Secure Routing Protocol Utilizing Cross Layer Design for Mobile Adhoc Networks. 2018 Fourth International Conference on Computing Communication Control and Automation (ICCUBEA). :1-6.

Cross layer based approaches are increasingly becoming popular in Manet (Mobile Adhoc Network). As Manet are constrained with issues as low battery, limited bandwidth, link breakage and dynamic topology, cross layer based designs are trying to remove such barriers and trying to make Manet more scalable. Cross layer designs are also facing attacking problem and ensuring the security of network to defend the attack is must. In this paper we discuss about technique to optimize the performance by minimizing delay and overhead of secure cross layer routing protocol. We have designed SCLPC (Secure cross layer based Power control) protocol. But when security is imposed using AASR (Authenticated and anonymous secure routing), the network metrics as end to end delay and control overhead is disturbed. To optimize the network performance here we proposed OSCLPC (Optimized secure cross layer based power control protocol). The proposed OSCLPC has been evaluated using SHORT (Self healing and optimizing route technique). The OSCLPC is simulated in ns2 and it is giving the better performance compared with SCLPC.

2019-02-14
Torres, Christof Ferreira, Schütte, Julian, State, Radu.  2018.  Osiris: Hunting for Integer Bugs in Ethereum Smart Contracts. Proceedings of the 34th Annual Computer Security Applications Conference. :664-676.

The capability of executing so-called smart contracts in a decentralised manner is one of the compelling features of modern blockchains. Smart contracts are fully fledged programs which cannot be changed once deployed to the blockchain. They typically implement the business logic of distributed apps and carry billions of dollars worth of coins. In that respect, it is imperative that smart contracts are correct and have no vulnerabilities or bugs. However, research has identified different classes of vulnerabilities in smart contracts, some of which led to prominent multi-million dollar fraud cases. In this paper we focus on vulnerabilities related to integer bugs, a class of bugs that is particularly difficult to avoid due to some characteristics of the Ethereum Virtual Machine and the Solidity programming language. In this paper we introduce Osiris – a framework that combines symbolic execution and taint analysis, in order to accurately find integer bugs in Ethereum smart contracts. Osiris detects a greater range of bugs than existing tools, while providing a better specificity of its detection. We have evaluated its performance on a large experimental dataset containing more than 1.2 million smart contracts. We found that 42,108 contracts contain integer bugs. Besides being able to identify several vulnerabilities that have been reported in the past few months, we were also able to identify a yet unknown critical vulnerability in a couple of smart contracts that are currently deployed on the Ethereum blockchain.

2018-06-04
2019-04-05
Dong, X., Hu, J., Cui, Y..  2018.  Overview of Botnet Detection Based on Machine Learning. 2018 3rd International Conference on Mechanical, Control and Computer Engineering (ICMCCE). :476-479.

With the rapid development of the information industry, the applications of Internet of things, cloud computing and artificial intelligence have greatly affected people's life, and the network equipment has increased with a blowout type. At the same time, more complex network environment has also led to a more serious network security problem. The traditional security solution becomes inefficient in the new situation. Therefore, it is an important task for the security industry to seek technical progress and improve the protection detection and protection ability of the security industry. Botnets have been one of the most important issues in many network security problems, especially in the last one or two years, and China has become one of the most endangered countries by botnets, thus the huge impact of botnets in the world has caused its detection problems to reset people's attention. This paper, based on the topic of botnet detection, focuses on the latest research achievements of botnet detection based on machine learning technology. Firstly, it expounds the application process of machine learning technology in the research of network space security, introduces the structure characteristics of botnet, and then introduces the machine learning in botnet detection. The security features of these solutions and the commonly used machine learning algorithms are emphatically analyzed and summarized. Finally, it summarizes the existing problems in the existing solutions, and the future development direction and challenges of machine learning technology in the research of network space security.

2019-06-10
Tran, T. K., Sato, H., Kubo, M..  2018.  One-Shot Learning Approach for Unknown Malware Classification. 2018 5th Asian Conference on Defense Technology (ACDT). :8-13.

Early detection of new kinds of malware always plays an important role in defending the network systems. Especially, if intelligent protection systems could themselves detect an existence of new malware types in their system, even with a very small number of malware samples, it must be a huge benefit for the organization as well as the social since it help preventing the spreading of that kind of malware. To deal with learning from few samples, term ``one-shot learning'' or ``fewshot learning'' was introduced, and mostly used in computer vision to recognize images, handwriting, etc. An approach introduced in this paper takes advantage of One-shot learning algorithms in solving the malware classification problem by using Memory Augmented Neural Network in combination with malware's API calls sequence, which is a very valuable source of information for identifying malware behavior. In addition, it also use some advantages of the development in Natural Language Processing field such as word2vec, etc. to convert those API sequences to numeric vectors before feeding to the one-shot learning network. The results confirm very good accuracies compared to the other traditional methods.

2019-09-09
Gutzwiller, Robert, Ferguson-Walter, Kimberly, Fugate, Sunny, Rogers, Andrew.  2018.  “Oh, look, a butterfly!" A framework for distracting attackers to improve cyber defense..

Inverting human factors can aid in cyber defense by flipping well-known guidelines and using them to degrade and disrupt the performance of a cyber attacker. There has been significant research on how we perform cyber defense tasks and how we should present information to operators, cyber defenders, and analysts to make them more efficient and more effective. We can actually create these situations just as easily as we can mitigate them. Oppositional human factors are a new way to apply well-known research on human attention allocation to disrupt potential cyber attackers and provide much-needed asymmetric benefits to the defender.

2019-01-24
Paulette Koronkevich.  2018.  Obsidian in the Rough: A Case Study Evaluation of a New Blockchain Programming Language. The ACM SIGPLAN conference on Systems, Programming, Languages and Applications: Software for Humanity (SPLASH).

Blockchains are one solution for secure distributed interaction, but security vulnerabilities have already been exposed in existing programs. Obsidian, a new blockchain programming language, seeks to prevent some of these vulnerabilities using typestate and linearity. We evaluate the current design of Obsidian by implementing a blockchain application for parametric insurance as a case study. We compare this implementation to one written in Solidity, and find that Obsidian can provide stronger safety guarantees.

2023-01-30
Koronkevich, Paulette.  2018.  Obsidian in the Rough: A Case Study Evaluation of a New Blockchain Programming Language. The ACM SIGPLAN conference on Systems, Programming, Languages and Applications: Software for Humanity.

Blockchains are one solution for secure distributed interaction, but security vulnerabilities have already been exposed in existing programs. Obsidian, a new blockchain programming language, seeks to prevent some of these vulnerabilities using typestate and linearity. We evaluate the current design of Obsidian by implementing a blockchain application for parametric insurance as a case study. We compare this implementation to one written in Solidity, and find that Obsidian can provide stronger safety guarantees.

2019-01-16
Hossain, M., Xie, J..  2018.  Off-sensing and Route Manipulation Attack: A Cross-Layer Attack in Cognitive Radio based Wireless Mesh Networks. IEEE INFOCOM 2018 - IEEE Conference on Computer Communications. :1376–1384.
Cognitive Radio (CR) has garnered much attention in the last decade, while the security issues are not fully studied yet. Existing research on attacks and defenses in CR - based networks focuses mostly on individual network layers, whereas cross-layer attacks remain fortified against single-layer defenses. In this paper, we shed light on a new vulnerability in cross-layer routing protocols and demonstrate how a perpetrator can exploit this vulnerability to manipulate traffic flow around it. We propose this cross-layer attack in CR-based wireless mesh networks (CR-WMNs), which we call off-sensing and route manipulation (OS-RM) attack. In this cross-layer assault, off-sensing attack is launched at the lower layers as the point of attack but the final intention is to manipulate traffic flow around the perpetrator. We also introduce a learning strategy for a perpetrator, so that it can gather information from the collaboration with other network entities and capitalize this information into knowledge to accelerate its malice intentions. Simulation results show that this attack is far more detrimental than what we have experienced in the past and need to be addressed before commercialization of CR-based networks.
2019-03-04
Berscheid, A., Makarov, Y., Hou, Z., Diao, R., Zhang, Y., Samaan, N., Yuan, Y., Zhou, H..  2018.  An Open-Source Tool for Automated Power Grid Stress Level Prediction at Balancing Authorities. 2018 IEEE/PES Transmission and Distribution Conference and Exposition (T D). :1–5.
The behavior of modern power systems is becoming more stochastic and dynamic, due to the increased penetration of variable generation, demand response, new power market structure, extreme weather conditions, contingencies, and unexpected events. It is critically important to predict potential system operational issues so that grid planners and operators can take preventive actions to mitigate the impact, e.g., lack of operational reserves. In this paper, an innovative software tool is presented to assist power grid operators in a balancing authority in predicting the grid stress level over the next operating day. It periodically collects necessary information from public domain such as weather forecasts, electricity demand, and automatically estimates the stress levels on a daily basis. Advanced Neural Network and regression tree algorithms are developed as the prediction engines to achieve this goal. The tool has been tested on a few key balancing authorities and successfully predicted the growing system peak load and increased stress levels under extreme heat waves.
2020-06-12
Latif, M. Kamran, Jacinto, H S., Daoud, Luka, Rafla, Nader.  2018.  Optimization of a Quantum-Secure Sponge-Based Hash Message Authentication Protocol. 2018 IEEE 61st International Midwest Symposium on Circuits and Systems (MWSCAS). :984—987.

Hash message authentication is a fundamental building block of many networking security protocols such as SSL, TLS, FTP, and even HTTPS. The sponge-based SHA-3 hashing algorithm is the most recently developed hashing function as a result of a NIST competition to find a new hashing standard after SHA-1 and SHA-2 were found to have collisions, and thus were considered broken. We used Xilinx High-Level Synthesis to develop an optimized and pipelined version of the post-quantum-secure SHA-3 hash message authentication code (HMAC) which is capable of computing a HMAC every 280 clock-cycles with an overall throughput of 604 Mbps. We cover the general security of sponge functions in both a classical and quantum computing standpoint for hash functions, and offer a general architecture for HMAC computation when sponge functions are used.

2018-11-19
Rauchberger, Julian, Schrittwieser, Sebastian, Dam, Tobias, Luh, Robert, Buhov, Damjan, Pötzelsberger, Gerhard, Kim, Hyoungshick.  2018.  The Other Side of the Coin: A Framework for Detecting and Analyzing Web-Based Cryptocurrency Mining Campaigns. Proceedings of the 13th International Conference on Availability, Reliability and Security. :18:1–18:10.

Mining for crypto currencies is usually performed on high-performance single purpose hardware or GPUs. However, mining can be easily parallelized and distributed over many less powerful systems. Cryptojacking is a new threat on the Internet and describes code included in websites that uses a visitor's CPU to mine for crypto currencies without the their consent. This paper introduces MiningHunter, a novel web crawling framework which is able to detect mining scripts even if they obfuscate their malicious activities. We scanned the Alexa Top 1 million websites for cryptojacking, collected more than 13,400,000 unique JavaScript files with a total size of 246 GB and found that 3,178 websites perform cryptocurrency mining without their visitors' consent. Furthermore, MiningHunter can be used to provide an in-depth analysis of cryptojacking campaigns. To show the feasibility of the proposed framework, three of such campaigns are examined in detail. Our results provide the most comprehensive analysis to date of the spread of cryptojacking on the Internet.

2020-11-17
Qian, K., Parizi, R. M., Lo, D..  2018.  OWASP Risk Analysis Driven Security Requirements Specification for Secure Android Mobile Software Development. 2018 IEEE Conference on Dependable and Secure Computing (DSC). :1—2.
The security threats to mobile applications are growing explosively. Mobile apps flaws and security defects open doors for hackers to break in and access sensitive information. Defensive requirements analysis should be an integral part of secure mobile SDLC. Developers need to consider the information confidentiality and data integrity, to verify the security early in the development lifecycle rather than fixing the security holes after attacking and data leaks take place. Early eliminating known security vulnerabilities will help developers increase the security of apps and reduce the likelihood of exploitation. However, many software developers lack the necessary security knowledge and skills at the development stage, and that's why Secure Mobile Software Development education is very necessary for mobile software engineers. In this paper, we propose a guided security requirement analysis based on OWASP Mobile Top ten security risk recommendations for Android mobile software development and its traceability of the developmental controls in SDLC. Building secure apps immune to the OWASP Mobile Top ten risks would be an effective approach to provide very useful mobile security guidelines.
2019-02-08
Islam, Mohammad A., Ren, Shaolei.  2018.  Ohm's Law in Data Centers: A Voltage Side Channel for Timing Power Attacks. Proceedings of the 2018 ACM SIGSAC Conference on Computer and Communications Security. :146-162.

Maliciously-injected power load, a.k.a. power attack, has recently surfaced as a new egregious attack vector for dangerously compromising the data center availability. This paper focuses on the emerging threat of power attacks in a multi-tenant colocation data center, an important type of data center where multiple tenants house their own servers and share the power distribution system. Concretely, we discover a novel physical side channel –- a voltage side channel –- which leaks the benign tenants' power usage information at runtime and helps an attacker precisely time its power attacks. The key idea we exploit is that, due to the Ohm's Law, the high-frequency switching operation (40\textasciitilde100kHz) of the power factor correction circuit universally built in today's server power supply units creates voltage ripples in the data center power lines. Importantly, without overlapping the grid voltage in the frequency domain, the voltage ripple signals can be easily sensed by the attacker to track the benign tenants' runtime power usage and precisely time its power attacks. We evaluate the timing accuracy of the voltage side channel in a real data center prototype, demonstrating that the attacker can extract benign tenants' power pattern with a great accuracy (correlation coefficient = 0.90+) and utilize 64% of all the attack opportunities without launching attacks randomly or consecutively. Finally, we highlight a few possible defense strategies and extend our study to more complex three-phase power distribution systems used in large multi-tenant data centers.

2019-02-25
Xu, H., Hu, L., Liu, P., Xiao, Y., Wang, W., Dayal, J., Wang, Q., Tang, Y..  2018.  Oases: An Online Scalable Spam Detection System for Social Networks. 2018 IEEE 11th International Conference on Cloud Computing (CLOUD). :98–105.
Web-based social networks enable new community-based opportunities for participants to engage, share their thoughts, and interact with each other. Theses related activities such as searching and advertising are threatened by spammers, content polluters, and malware disseminators. We propose a scalable spam detection system, termed Oases, for uncovering social spam in social networks using an online and scalable approach. The novelty of our design lies in two key components: (1) a decentralized DHT-based tree overlay deployment for harvesting and uncovering deceptive spam from social communities; and (2) a progressive aggregation tree for aggregating the properties of these spam posts for creating new spam classifiers to actively filter out new spam. We design and implement the prototype of Oases and discuss the design considerations of the proposed approach. Our large-scale experiments using real-world Twitter data demonstrate scalability, attractive load-balancing, and graceful efficiency in online spam detection for social networks.
2019-12-17
Zhao, Shixiong, Gu, Rui, Qiu, Haoran, Li, Tsz On, Wang, Yuexuan, Cui, Heming, Yang, Junfeng.  2018.  OWL: Understanding and Detecting Concurrency Attacks. 2018 48th Annual IEEE/IFIP International Conference on Dependable Systems and Networks (DSN). :219-230.
Just like bugs in single-threaded programs can lead to vulnerabilities, bugs in multithreaded programs can also lead to concurrency attacks. We studied 31 real-world concurrency attacks, including privilege escalations, hijacking code executions, and bypassing security checks. We found that compared to concurrency bugs' traditional consequences (e.g., program crashes), concurrency attacks' consequences are often implicit, extremely hard to be observed and diagnosed by program developers. Moreover, in addition to bug-inducing inputs, extra subtle inputs are often needed to trigger the attacks. These subtle features make existing tools ineffective to detect concurrency attacks. To tackle this problem, we present OWL, the first practical tool that models general concurrency attacks' implicit consequences and automatically detects them. We implemented OWL in Linux and successfully detected five new concurrency attacks, including three confirmed and fixed by developers, and two exploited from previously known and well-studied concurrency bugs. OWL has also detected seven known concurrency attacks. Our evaluation shows that OWL eliminates 94.1% of the reports generated by existing concurrency bug detectors as false positive, greatly reducing developers' efforts on diagnosis. All OWL source code, concurrency attack exploit scripts, and results are available on github.com/hku-systems/owl.
2019-02-21
Xie, S., Wang, G..  2018.  Optimization of parallel turnings using particle swarm intelligence. 2018 Tenth International Conference on Advanced Computational Intelligence (ICACI). :230–234.
Machining process parameters optimization is of concern in machining fields considering machining cost factor. In order to solve the optimization problem of machining process parameters in parallel turning operations, which aims to reduce the machining cost, two PSO-based optimization approaches are proposed in this paper. According to the divide-and-conquer idea, the problem is divided into some similar sub-problems. A particle swarm optimization then is derived to conquer each sub-problem to find the optimal results. Simulations show that, comparing to other optimization approaches proposed previously, the proposed two PSO-based approaches can get optimal machining parameters to reduce both the machining cost (UC) and the computation time.
2019-02-13
Irmak, E., Erkek, İ.  2018.  An overview of cyber-attack vectors on SCADA systems. 2018 6th International Symposium on Digital Forensic and Security (ISDFS). :1–5.

Most of the countries evaluate their energy networks in terms of national security and define as critical infrastructure. Monitoring and controlling of these systems are generally provided by Industrial Control Systems (ICSs) and/or Supervisory Control and Data Acquisition (SCADA) systems. Therefore, this study focuses on the cyber-attack vectors on SCADA systems to research the threats and risks targeting them. For this purpose, TCP/IP based protocols used in SCADA systems have been determined and analyzed at first. Then, the most common cyber-attacks are handled systematically considering hardware-side threats, software-side ones and the threats for communication infrastructures. Finally, some suggestions are given.

2020-10-05
Scott-Hayward, Sandra, Arumugam, Thianantha.  2018.  OFMTL-SEC: State-based Security for Software Defined Networks. 2018 IEEE Conference on Network Function Virtualization and Software Defined Networks (NFV-SDN). :1–7.
Dynamic network security services have been proposed exploiting the benefits of Software Defined Networking (SDN) and Network Functions Virtualization (NFV) technologies. However, many of these services rely on controller interaction, which presents a performance and scalability challenge, and a threat vector. To overcome the performance issue, stateful data-plane designs have been proposed. Unfortunately, these solutions do not offer protection from attacks that exploit the SDN implementation of network functions such as topology and path update, or services such as the Address Resolution Protocol (ARP). In this work, we propose state-based SDN security protection mechanisms. Our stateful security data plane solution, OFMTL-SEC, is designed to provide protection against attacks on SDN and traditional network services. Specifically, we present a novel data plane protection against configuration-based attacks in SDN and against ARP spoofing. OFMTL-SEC is compared with the state-of-the-art solutions and offers increased security to SDNs with negligible performance impact.
2019-09-05
Wendzel, Steffen, Eller, Daniela, Mazurczyk, Wojciech.  2018.  One Countermeasure, Multiple Patterns: Countermeasure Variation for Covert Channels. Proceedings of the Central European Cybersecurity Conference 2018. :1:1-1:6.

Network covert channels enable stealthy communications for malware and data exfiltration. For this reason, the development of effective countermeasures for covert channels is important for the protection of individuals and organizations. However, due to the number of available covert channel techniques, it can be considered impractical to develop countermeasures for all existing covert channels. In recent years, researchers started to develop countermeasures that (instead of only countering one particular hiding technique) can be applied to a whole family of similar hiding techniques. These families are referred to as hiding patterns. The main contribution of this paper is that we extend the idea of hiding patterns by introducing the concept of countermeasure variation. Countermeasure variation is the slight modification of a given countermeasure that was designed to detect covert channels of one specific hiding pattern so that the countermeasure can also detect covert channels that are representing other hiding patterns. We exemplify countermeasure variation using the compressibility score originally presented by Cabuk et al. The compressibility score is used to detect covert channels of the 'inter-packet times' pattern and we show that countermeasure variation allows the application of the compressibility score to detect covert channels of the 'size modulation' pattern, too.

2019-03-18
Albarakati, A., Moussa, B., Debbabi, M., Youssef, A., Agba, B. L., Kassouf, M..  2018.  OpenStack-Based Evaluation Framework for Smart Grid Cyber Security. 2018 IEEE International Conference on Communications, Control, and Computing Technologies for Smart Grids (SmartGridComm). :1–6.

The rapid evolution of the power grid into a smart one calls for innovative and compelling means to experiment with the upcoming expansions, and analyze their behavioral response under normal circumstances and when targeted by attacks. Such analysis is fundamental to setting up solid foundations for the smart grid. Smart grid Hardware-In-the-Loop (HIL) co-simulation environments serve as a key approach to answer questions on the systems components, functionality, security concerns along with analysis of the system outcome and expected behavior. In this paper, we introduce a HIL co-simulation framework capable of simulating the smart grid actions and responses to attacks targeting its power and communication components. Our testbed is equipped with a real-time power grid simulator, and an associated OpenStack-based communication network. Through the utilized communication network, we can emulate a multitude of attacks targeting the power system, and evaluating the grid response to those attacks. Moreover, we present different illustrative cyber attacks use cases, and analyze the smart grid behavior in the presence of those attacks.

2018-06-07
Wang, Wenhao, Xu, Xiaoyang, Hamlen, Kevin W..  2017.  Object Flow Integrity. Proceedings of the 2017 ACM SIGSAC Conference on Computer and Communications Security. :1909–1924.
Object flow integrity (OFI) augments control-flow integrity (CFI) and software fault isolation (SFI) protections with secure, first-class support for binary object exchange across inter-module trust boundaries. This extends both source-aware and source-free CFI and SFI technologies to a large class of previously unsupported software: those containing immutable system modules with large, object-oriented APIs—which are particularly common in component-based, event-driven consumer software. It also helps to protect these inter-module object exchanges against confused deputy-assisted vtable corruption and counterfeit object-oriented programming attacks. A prototype implementation for Microsoft Component Object Model demonstrates that OFI is scalable to large interfaces on the order of tens of thousands of methods, and exhibits low overheads of under 1% for some common-case applications. Significant elements of the implementation are synthesized automatically through a principled design inspired by type-based contracts.