부산대학교 도서관

The allure of malware, with its tremendous potential to infiltrate and disrupt digital systems, is understandable. Criminally motivated malware is now directed at all levels and corners of the cyber domain, from servers to endpoints, laptops, smartphones, tablets, and industrial control systems. A thriving underground industry today produces ever-increasing quantities of malware for a wide variety of platforms, which bad actors seem able to deploy with relative impunity. The urge to fight back with “good” malware is understandable. In this paper we review and assess the arguments for and against the use of malicious code for either active defense or direct offense. Our practical experiences analyzing and defending against malicious code suggest that the effect of deployment is hard to predict with accuracy. There is tremendous scope for unintended consequences and loss of control over the code itself. Criminals do not feel restrained by these factors and appear undeterred by moral dilemmas like collateral damage, but we argue that persons or entities considering the use of malware for “justifiable offense” or active defense need to fully understand the issues around scope, targeting, control, blowback, and arming the adversary. Using existing open source literature and commentary on this topic we review the arguments for and against the use of “malicious” code for “righteous” purposes, introducing the term “righteous malware”. We will cite select instances of prior malicious code deployment to reveal lessons learned for future missions. In the process, we will refer to a range of techniques employed by criminally-motivated malware authors to evade detection, amplify infection, leverage investment, and execute objectives that range from denial of service to information stealing, fraudulent, revenue generation, blackmail and surveillance. Examples of failure to retain control of criminally motivated malicious code development will also be examined for what they may tell us about code persistence and life cycles. In closing, we will present our considered opinions on the risks of weaponizing code.