Archives for 2007

Yesterday the California Secretary of State released the reports of three source code study teams that analyzed the source code of e-voting systems from Diebold, Hart InterCivic, and Sequoia.

• Diebold systems
• Hart InterCivic systems
• Sequoia systems

All three reports found many serious vulnerabilities. It seems likely that computer viruses could be constructed that could infect any of the three systems, spread between voting machines, and steal votes on the infected machines. All three systems use central tabulators (machines at election headquarters that accumulate ballots and report election results) that can be penetrated without great effort.

It’s hard to convey the magnitude of the problems in a short blog post. You really have read through the reports – the shortest one is 78 pages – to appreciate the sheer volume and diversity of severe vulnerabilities.

It is interesting (at least to me as a computer security guy) to see how often the three companies made similar mistakes. They misuse cryptography in the same ways: using fixed unchangeable keys, using ciphers in ECB mode, using a cyclic redundancy code for data integrity, and so on. Their central tabulators use poorly protected database software. Their code suffers from buffer overflows, integer overflow errors, and format string vulnerabilities. They store votes in a way that compromises the secret ballot.

Some of these are problems that the vendors claimed to have fixed years ago. For example, Diebold claimed (p. 11) in 2003 that its use of hard-coded passwords was “resolved in subsequent versions of the software”. Yet the current version still uses at least two hard-coded passwords – one is “diebold” (report, p. 46) and another is the eight-byte sequence 1,2,3,4,5,6,7,8 (report, p. 45).

Similarly, Diebold in 2003 ridiculed (p. 6) the idea that their software could suffer from buffer overflows: “Unlike a Web server or other Internet enabled applications, the code is not vulnerable to most ‘buffer overflow attacks’ to which the authors [Kohno et al.] refer. This form of attack is almost entirely inapplicable to our application. In the limited number of cases in which it would apply, we have taken the steps necessary to ensure correctness.” Yet the California source code study found several buffer overflow vulnerabilities in Diebold’s systems (e.g., issues 5.1.6, 5.2.3 (“multiple buffer overflows”), and 5.2.18 in the report).

As far as I can tell, major news outlets haven’t taken much notice of these reports. That in itself may be the most eloquent commentary on the state of e-voting: reports of huge security holes in e-voting systems are barely even newsworthy any more.

I wrote Monday about the California Secretary of State’s partial release of report from the state’s e-voting study. Four subteams submitted reports to the Secretary, but as yet only the “red team” and accessibility teams’ reports have been released. The other two sets of reports, from the source code review and documentation review teams, are still being withheld.

The Secretary even held a public hearing on Monday about the study, without having released all of the reports. This has led to a certain amount of confusion, as many press reports and editorials (e.g. the Mercury News editorial) about the study seem to assume that the full evaluation results have been reported. The vendors and some county election officials have encouraged this misimpression – some have even criticized the study for failing to consider issues that are almost certainly addressed in the missing reports.

With the Secretary having until Friday to decide whether to decertify any e-voting systems for the February 2008 primary election, the obvious question arises: Why is the Secretary withholding the other reports?

Here’s the official explanation, from the Secretary’s site:

The document review teams and source code review teams submitted their reports on schedule. Their reports will be posted as soon as the Secretary of State ensures the reports do not inadvertently disclose security-sensitive information.

This explanation is hard to credit. The study teams were already tasked to separate their reports into a public body and a private appendix, with sensitive exploit-oriented details put in the private appendix that would go only to the Secretary and the affected vendor. Surely the study teams are much better qualified to determine the security implications of releasing a particular detail than the lawyers in the Secretary’s office are.

More likely, the Secretary is worried about the political implications of releasing the reports. Given this, it seems likely that the withheld reports are even more damning than the ones released so far.

If the red team reports, which reported multiple vulnerabilities of the most serious kind, are the good news, how bad must the bad news be?

UPDATE (2:45 PM EDT, August 2): The source code review reports are now up on the Secretary of State’s site. They’re voluminous so I won’t be commenting on them immediately. I’ll post my reactions tomorrow.

A major study of three e-voting systems, commissioned by the California Secretary of State’s office, reported Friday that all three had multiple serious vulnerabilities.

The study examined systems from Diebold, Hart InterCivic, and Sequoia; each system included a touch-screen machine, an optical-scan machine, and the associated backend control and tabulation machine. Each system was studied by three teams: a “red team” did a hands-on study of the machines, a “source code team” examined the software source code for the system, and a “documentation team” examined documents associated with the system and its certification. (An additional team studied the accessibility of the three systems – an important topic but beyond the scope of this post.)

(I did not participate in the study. An early press release from the state listed me as a participant but that was premature. I ultimately had to withdraw before the study began, due to a scheduling issue.)

So far only the red team (and accessibility) reports have been released, which makes one wonder what is in the remaining reports. Here are the reports so far:

• Red team overview
• Red team report on Diebold systems
• Red team report on Hart Intercivic systems
• Red team report on Sequoia systems
• Accessibility team report

The bottom-line paragraph from the red team overview says this (section 6.4):

The red teams demonstrated that the security mechanisms provided for all systems analyzed were inadequate to ensure accuracy and integrity of the election results and of the systems that provide those results.

The red teams all reported having inadequate time to fully plumb the systems’ vulnerabilities (section 4.0):

The short time allocated to this study has several implications. The key one is that the results presented in this study should be seen as a “lower bound”; all team members felt that they lacked sufficient time to conduct a thorough examination, and consequently may have missed other serious vulnerabilities. In particular, Abbott’s team [which studied the Diebold and Hart systems] reported that it believed it was close to finding several other problems, but stopped in order to prepare and deliver the required reports on time. These unexplored avenues are presented in the reports, so that others may pursue them. Vigna’s and Kemmerer’s team [which studied the Sequoia system] also reported that they were confident further testing would reveal additional security issues.

Despite the limited time, the teams found ways to breach the physical security of all three systems using only “ordinary objects” (presumably paper clips, coins, pencil erasers, and the like); they found ways to modify or overwrite the basic control software in all three voting machines; and they were able to penetrate the backend tabulator system and manipulate election records.

The source code and documentation studies have not yet been released. To my knowledge, the state has not given a reason for the delay in releasing these reports.

The California Secretary of State reportedly has until Friday to decide whether to allow these systems to be used in the state’s February 2008 primary election.

[UPDATE: A public hearing on the study is being webcast live at 10:00 AM Pacific today.]