Going Critical

January 2013 was a bit of a rough month for users of Ruby on Rails and rubygems. org. Two critical security flaws were found in Ruby on Rails, and rubygems. org was broken into (luckily, not by a malicious hacker). In this article, I will look at exactly what caused these security vulnerabilities and the break-in to earn “critical” ratings, what the vendors did when a critical issue came up, and what users can do to help keep their software secure.

Critical Issues

One of the most important criteria in judging whether a security issue is critical or not is the severity of exploitation (see the “CVSS2 Scores” box). An attack that allows remote code execution as a privileged user or root is a whole lot worse than a simple denial of service condition. On the other hand, a denial of service that can be triggered remotely with a single network packet and make it through the Internet (e.g., not just on the same local subnet) might also be rated “critical.”