Slideshow: Next Generation Defense Technologies
|(click for larger image and for full photo gallery)|
"The lesson learned is not to be more timid, but more aggressive about solving the problem in exactly the way that we have chosen," Paul Stenbjorn, director of information services for the city's board of elections and ethics (BOEE), wrote on the board's website in response to criticism this week. "Our task is to continue pursuing a robust, secure digital means for overseas voters to cast their ballot rather than resorting to email or fax."
As part of an ongoing public evaluation of the system's privacy and security, researchers at the University of Michigan last month discovered vulnerabilities that gave them "almost total control of the server software, including the ability to change votes and reveal voters' secret ballots," according to a blog post by Michigan assistant professor Alex Halderman, who headed up the university's efforts.
D.C.'s system allows users to log onto a website with a unique pin, download a PDF ballot and either return it by mail or upload the completed ballot via the site. The back-end server then encrypts and stores the ballots.
After 36 hours of probing the software, the researchers determined that while the server replaced the user-defined filename for the uploaded PDF file with an automatically generated one, it kept the file extension provided by the voter, and by formatting the extension as code, the researchers were able to cause the server to execute commands that a privileged user might have, such as collecting system passwords and encryption keys and viewing and modifying completed ballots.
In response, the city not only suspended the electronic voting option, but also temporarily stopped testing the system in order to fix the vulnerability. However, testing resumed on Wednesday.
Stennbjorn noted that the board of elections' public tests originally grew out of its dissatisfaction in the lack of best practices, risk models, and collaborative frameworks developed at a National Institute for Standards and Technology workshop this year, and that it anticipated the possibility of just this result.
"Our public test had been hacked, which you would think would have been an objectively bad thing for the BOEE," Stenbjorn wrote. "You'd think wrong. Our goal was simple: determine if the application as developed passed muster, and if not, determine better mechanisms for security, transport, and usability for future releases."
For his part, Michigan's Halderman expressed concern that such systems might contain other security flaws. "If this particular problem had not existed, I'm confident we would have found another way to attack the system," he wrote. "Everything we've seen suggests that the design is brittle. It may someday be possible to build a secure method for submitting ballots over the Internet, but in the meantime, such systems should be presumed to be vulnerable based on the limitations of today's security technology."