This paper presents a game theoretic analysis of the relationship between an information technology platform’s market share, its level of security, and the extent to which malware creators (hackers) target a platform in order to proliferate via the platform’s network externalities. In equilibrium, a platform’s market share is shown to be the square root of the ratio of its competitor’s vulnerability to its own vulnerability. This implies that in order to maintain market share, platform leaders must make increasing investments in cybersecurity, thereby decreasing the platform’s vulnerability. Introduction Malware, a term that combines malicious with software, refers to a computer infection program designed to compromise, damage, or infiltrate a computer, server or network without the user’s knowledge or consent, often for profitable gain. Examples of self-replicating malware include viruses and worms. The potential for malware has been recognized since the dawn of personal computing itself. Hiltzik (1999) recounts a 1978 episode at Xerox’s revolutionary PARC research facility where an employee created a worm whose code became corrupted and caused scores of desktop computers connected to PARC’s Ethernet to repeatedly crash. According to a joint study by International Data Corporation and National Singapore University, for 2014 the annual cost of malware was expected to be over $491 billion a year (Robinson 2014). In addition, consumers would spend 1.2 billion hours dealing with the aftereffects of malware. The direct cost alone would rank malware as the 26 largest country in the world in terms of GDP. In such a high stakes environment it is necessary to understand the strategic incentives facing those who provide security for information technology platforms (e.g., PCs, tablets, smartphones), users who select this technology, and malware that targets users through platforms. As the famous bank robber Willie Sutton reportedly explained, he robbed banks, “because that’s where the money is.” Similarly, hackers write malware to target where users are, and this is determined by the market share of a platform. Everything else held equal, hackers prefer a platform with a larger installed base (Honeynet Project 2004). This paper provides a game theoretic characterization of the relationship between market share, quality (security) of a platform, and the relative degree to which malware creators (hackers) target a platform. Two of the three of these variables: market share and the distribution of malware across platforms, are 11 The use of the term “platform” is widespread in the literature on the economics of two-sided markets, where a platform allows distinct user groups to interface, thereby providing each other with network benefits, often based on economies of scale. Technological devices or systems are quintessential examples of economic platforms because they create network externalities by matching users and application providers.

中文翻译：

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恶意软件和市场份额

本文对信息技术平台的市场份额，其安全级别以及恶意软件创建者（黑客）针对该平台以通过该平台的网络外部性进行扩散的程度之间的关系进行了博弈论分析。在均衡状态下，平台的市场份额被证明是其竞争对手的脆弱性与其自身脆弱性之比的平方根。这意味着，为了保持市场份额，平台领导者必须加大对网络安全的投资，从而降低平台的脆弱性。简介恶意软件是一个将恶意软件与软件结合在一起的术语，是指一种计算机感染程序，旨在在未经用户知情或同意的情况下危害，破坏或渗透计算机，服务器或网络，通常是为了牟利。自复制恶意软件的示例包括病毒和蠕虫。自从个人计算本身问世以来，就已经意识到了恶意软件的潜力。希尔兹克（Hiltzik，1999）在施乐的革命性PARC研究机构中叙述了1978年的一集，其中一名员工制造了一条蠕虫，蠕虫的代码被破坏，导致数十台连接到PARC以太网的台式计算机反复崩溃。根据国际数据公司和新加坡国立大学的联合研究，2014年恶意软件的年度成本预计每年超过4910亿美元（Robinson 2014）。此外，消费者将花费12亿小时来应对恶意软件的后遗症。就直接成本而言，就GDP而言，恶意软件将其列为全球26个最大的国家。在如此高风险的环境中，有必要了解为信息技术平台（例如，PC，平板电脑，智能手机）提供安全保护的人员，选择该技术的用户以及通过平台锁定用户的恶意软件所面临的战略动机。据报道，著名的银行抢劫犯威利·萨顿（Willie Sutton）抢劫了银行，“因为那是钱。” 同样，黑客编写恶意软件来锁定用户所在的位置，这取决于平台的市场份额。在其他所有条件都相同的情况下，黑客更喜欢安装基础更大的平台（Honeynet Project 2004）。本文提供了市场理论，平台质量（安全性）与恶意软件创建者（黑客）针对平台的相对程度之间的关系的博弈论表征。这三个变量中的两个变量：市场份额和跨平台的恶意软件分布11术语“平台”的使用在双向市场经济学的文献中很普遍，其中平台允许不同的用户组接口，从而通常基于规模经济为彼此提供网络收益。技术设备或系统是经济平台的典型示例，因为它们通过匹配用户和应用程序提供商来创建网络外部性。