The Spread of the Witty Worm
The folks at UCSD Computer Science and Engineering and the Cooperative Association for Internet Data Analysis (CAIDA) put their “Network Telescope” to good work in analyzing the spread of the Witty Worm. From their analysis:
Witty was the first widely propagated Internet worm to carry a destructive payload. Witty was started in an organized manner with an order of magnitude more ground-zero hosts than any previous worm. Witty represents the shortest known interval between vulnerability disclosure and worm release — it began to spread the day after the ISS vulnerability was publicized. Witty spread through a host population in which every compromised host was doing something proactive to secure their computers and networks. Witty spread through a population almost an order of magnitude smaller than that of previous worms, demonstrating the viability of worms as an automated mechanism to rapidly compromise machines on the Internet, even in niches without a software monopoly.
The conclusion is ominous:
Witty demonstrated that any minimally deployed piece of software with a remotely exploitable bug can be a vector for wide-scale compromise of host machines without any action on the part of a victim. The practical implications of this are staggering; with minimal skill, a malevolent individual could break into thousands of machines and use them for almost any purpose with little evidence of the perpetrator left on most of the compromised hosts.
The patch model for Internet security has failed spectacularly. To remedy this, there have been a number of suggestions for ways to try to shoehorn end users into becoming security experts, including making them financially liable for the consequences of their computers being hijacked by malware or miscreants. Notwithstanding the fundamental inequities involved in encouraging people sign on to the Internet with a single click, and then requiring them to fix flaws in software marketed to them as secure with technical skills they do not possess, many users do choose to protect themselves at their own expense by purchasing antivirus and firewall software. Making this choice is the gold-standard for end user behavior — they recognize both that security is important and that they do not possess the skills necessary to effect it themselves. When users participating in the best security practice that can be reasonably expected get infected with a virulent and damaging worm, we need to reconsider the notion that end user behavior can solve or even effectively mitigate the malicious software problem and turn our attention toward both preventing software vulnerabilities in the first place and developing large-scale, robust and reliable infrastructure that can mitigate current security problems without relying on end user intervention.