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Seals on NJ voting machines, October-December 2008

February 8, 2011 by

In my examination of New Jersey’s voting machines, I found that there were no tamper-indicating seals that prevented fiddling with the vote-counting software—just a plastic strap seal on the vote cartridge. And I was rather skeptical whether slapping seals on the machine would really secure the ROMs containing the software. I remembered Avi Rubin’s observations from a couple of years earlier, that I described in a previous post.

A bit of googling turned up this interesting 1996 article:


Vulnerability Assessment of Security Seals
Roger G. Johnston, Ph.D. and Anthony R.E. Garcia
Los Alamos National Laboratory

… We studied 94 different security seals, both passive and electronic, developed either commercially or by the United States Government. Most of these seals are in wide-spread use, including for critical applications. We learned how to defeat all 94 seals using rapid, inexpensive, low-tech methods.

In my expert report, I cited this scientific article to explain that seals would not be a panacea to solve the problems with the voting machine.

Soon after I delivered this report to the Court, the judge held a hearing in which she asked the defendants (the State of New Jersey) how they intended to secure these voting machines against tampering. A few weeks later, the State explained their new system: more seals.

For the November 2008 election, they slapped on three pieces of tape, a wire seal, and a “security screw cap”, in addition to the plastic strap seal that had already been in use. All these seals are in the general categories described by Johnston and Garcia as easy to defeat using “rapid, inexpensive, low-tech methods”.

Up to this point I knew in theory (by reading Avi Rubin and Roger Johnston) that tamper-indicating seals aren’t very secure, but I hadn’t really tried anything myself.

Here’s what is not so obvious: If you want to study how to lift and replace a seal without breaking it, or how to counterfeit a seal, you can’t practice on the actual voting machine (or other device) in the polling place! You need a few dozen samples of the seal, so that you can try different approaches, to see what works and what doesn’t. Then you need to practice these approaches over and over. So step 1 is to get a big bag of seals.

What I’ve discovered, by whipping out a credit card and trying it, is that the seal vendors are happy to sell you 100 seals, or 1000, or however many you need. They cost about 50 cents apiece, or more, depending on the seal. So I bought some seals. In addition, under Court order we got some samples from the State, but that wasn’t really necessary as all those seals are commercially available, as I found by a few minutes of googling.

The next step was to go down to my basement workshop and start experimenting. After about a day of thinking about the seals and trying things out, I cracked them all.

As I wrote in December 2008, all those seals are easily defeated.

  • The tamper-indicating tape can be lifted using a heat gun and a razor blade, then replaced with no indication of tampering.
  • The security screw cap can be removed using a screwdriver, then the
    serial-numbered top can be replaced (undamaged) onto a fresh (unnumbered) base.

  • The wire seal can be defeated using a #4 wood screw.
  • The plastic strap seal can be picked using a jeweler’s screwdriver.

For details and pictures, see “Seal Regime #2” in this paper.

Filed Under: Other Topics, Privacy & Security Tagged With: ,

Seals on NJ voting machines, 2004-2008

January 24, 2011 by

I have just released a new paper entitled “Security seals on voting machines: a case study“ and here I’ll explain how I came to write it.

Like many computer scientists, I became interested in the technology of vote-counting after the technological failure of hanging chads and butterfly ballots in 2000. In 2004 I visited my local polling place to watch the procedures for closing the polls, and I noticed that ballot cartridges were sealed by plastic strap seals like this one:

plastic strap seal

The pollworkers are supposed to write down the serial numbers on the official precinct report, but (as I later found when Ed Felten obtained dozens of these reports through an open-records request), about 50% of the time they forget to do this:

In 2008 when (as the expert witness in a lawsuit) I examined the hardware and software of New Jersey’s voting machines, I found that there were no security seals present that would impede opening the circuit-board cover to replace the vote-counting software. The vote-cartridge seal looks like it would prevent the cover from being opened, but it doesn’t.

There was a place to put a seal on the circuit-board cover, through the hole labeled “DO NOT REMOVE”, but there was no seal there:

Somebody had removed a seal, probably a voting-machine repairman who had to open the cover to replace the batteries, and nobody bothered to install a new one.

The problem with paperless electronic voting machines is that if a crooked political operative has access to install fraudulent software, that software can switch votes from one candidate to another. So, in my report to the Court during the lawsuit, I wrote,


10.6. For a system of tamper-evident seals to provide effective protection, the seals must be consistently installed, they must be truly tamper-evident, and they must be consistently inspected. With respect to the Sequoia AVC Advantage, this means that all five of the
following would have to be true. But in fact, not a single one of these is true in practice, as I will explain.

  1. The seals would have to be routinely in place at all times when an attacker might wish to access the Z80 Program ROM; but they are not.
  2. The cartridge should not be removable without leaving evidence of tampering with
    the seal; but plastic seals can be quickly defeated, as I will explain.

  3. The panel covering the main circuit board should not be removable without removing the [vote-cartridge] seal; but in fact it is removable without disturbing the seal.
  4. If a seal with a different serial number is substituted, written records would have to reliably catch this substitution; but I have found major gaps in these records in New Jersey.
  5. Identical replacement seals (with duplicate serial numbers) should not exist; but the evidence shows that no serious attempt is made to avoid duplication.

Those five criteria are just common sense about what would be a required in any effective system for protecting something using tamper-indicating seals. What I found was that (1) the seals aren’t always there; (2) even if they were, you can remove the cartridge without visible evidence of tampering with the seal and (3) you can remove the circuit-board cover without even disturbing the plastic-strap seal; (4) even if that hadn’t been true, the seal-inspection records are quite lackadaisical and incomplete; and (5) even if that weren’t true, since the counties tend to re-use the same serial numbers, the attacker could just obtain fresh seals with the same number!

Since the time I wrote that, I’ve learned from the seal experts that there’s a lot more to a seal use protocol than these five observations. I’ll write about that in the near future.

But first, I’ll write about the State of New Jersey’s slapdash response to my first examination of their seals. Stay tuned.

Filed Under: Other Topics, Privacy & Security Tagged With: ,

Monitoring all the electrical and hydraulic appliances in your house

January 4, 2011 by

Dan Wallach recently wrote about his smart electric meter, which keeps track of the second-by-second current draw of his whole house. But what he might like to know is, exactly what appliance is on at what time? How could you measure that?

You might think that one would have to instrument each different circuit at the breaker box, or every individual electric plug at the outlet. This would be expensive, not particularly for all the little sensors but for the labor of an electrician to install everything.

Recent “gee whiz” research by Professor Shwetak Patel‘s group at the University of Washington provides a really elegant solution. Every appliance you own–your refrigerator, your flat-screen TV, your toaster–has a different “electrical noise signature” that it draws from the wires in your house. When you turn it on, this signal is (inadvertently) sent through the electric wires to the circuit-breaker box. It’s not necessary (as one commenter suggested) to buy “smart appliances” that send purpose-designed on-off signals; your “dumb” appliances already send their own noise signatures.

Patel’s group built a device that you plug in to an electrical outlet, which figures out when your appliances are turning on and off. The device is equipped with a database of common signatures (it can tell one brand of TV from another!) and with machine-learning algorithms that figure out the unique characteristics of your particular devices (if you have two “identical” Toshiba TVs, it can tell them apart!). Patel’s device could be an extremely useful “green technology” to help consumers painlessly reduce their electricity consumption.

Patel can do the same trick on your water pipes. Each toilet flush or shower faucet naturally sends a different acoustic pressure signal, and a single sensor can monitor all your devices.

Of course, in addition to the “green” advantages of this technology, there are privacy implications. Even without your consent, the electric company and the water company are permitted to continuously measure your use of electricity and water; taken to the extreme, this monitoring alone could tell them exactly when you use each and every device in your house.

Filed Under: Privacy & Security Tagged With: ,

Unpeeling the mystique of tamper-indicating seals

December 7, 2010 by

As computer scientists have studied the trustworthiness of different voting technologies over the past decade, we notice that “security seals” are often used by election officials. It’s natural to wonder whether they really provide any real security, or whether they are just for show. When Professor Avi Rubin volunteered as an election judge (Marylandese for pollworker) in 2006, one of his observations that I found most striking was this:


Avi Rubin
“For example, I carefully studied the tamper tape that is used to guard the memory cards. In light of Hursti’s report, the security of the memory cards is critical. Well, I am 100% convinced that if the tamper tape had been peeled off and put back on, nobody except a very well trained professional would notice it. The tamper tape has a tiny version of the word “void” appear inside it after it has been removed and replaced, but it is very subtle. In fact, a couple of times, due to issues we had with the machines, the chief judge removed the tamper tape and then put it back. One time, it was to reboot a machine that was hanging when a voter was trying to vote. I looked at the tamper tape that was replaced and couldn’t tell the difference, and then it occurred to me that instead of rebooting, someone could mess with the memory card and replace the tape, and we wouldn’t have noticed. I asked if I could play with the tamper tape a bit, and they let me handle it. I believe I can now, with great effort and concentration, tell the difference between one that has been peeled off and one that has not. But, I did not see the judges using that kind of care every time they opened and closed them. As far as I’m concerned, the tamper tape does very little in the way of actual security, and that will be the case as long as it is used by lay poll workers, as opposed to CIA
agents.”

Avi is a first-rate expert in the field of computer security, in part because he’s a good experimentalist—as in, “I asked if I could play with the tamper tape.” To the nonexpert,
security seals have a mystique: there’s this device there, perhaps a special tape or perhaps a thing that looks like a little blue plastic padlock. Most of us encounter these devices in a context where we can’t “play with” them, because that would be breaking the rules: on voting machines, on our electric meter, or whatever. Since we don’t play with them, we can’t tell whether they are secure, and the mystique endures. As soon
as Avi played with one, he discovered that it’s not all that secure.

In fact, we have a word for a piece of tape that only gives the appearance of working:

band-aid: (2) a temporary way of dealing with a problem that will not really solve it (Macmillan Dictionary)

In the last couple of years I’ve been studying security seals on voting machines in New Jersey. For many decades New Jersey law has required that each voting machine be “sealed with a numbered seal”, just after it is prepared for each election (NJSA 19:48-6). Unfortunately it’s hard for legislators to write into the statutes exactly how well these seals must work. Are tamper-indicating seals used in elections really secure? I’ll address that question in my next few articles.

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NJ court permits release of post-trial briefs in voting case

October 27, 2010 by

In 2009 the Superior Court of New Jersey, Law Division, held a trial on the legality of using paperless direct-recording electronic (DRE) voting machines. Plaintiffs in the suit argued that because it’s so easy to replace the software in a DRE with fraudulent software that cheats in elections, DRE voting systems do not guarantee the substantive right to vote (and to have one’s vote counted) required by the New Jersey constitution and New Jersey statutory law.

I described this trial in three articles last year: trial update, summary of plaintiffs’ witnesses’ testimony, and summary of defense witnesses’ testimony.

Normally in a lawsuit, the courtroom is open. The public can attend all legal proceedings. Additionally, plaintiffs are permitted to explain their case to the public by releasing their post-trial briefs (“proposed findings of fact” and “proposed conclusions of law”). But in this suit the Attorney General of New Jersey, representing the defendants in this case, argued that the courtroom be closed for parts of the proceedings, and asked the Court to keep all post-trial documents from the public, indefinitely.

More than a year after the trial ended, the Court finally held a hearing to determine whether post-trial documents should be kept from the public. The Attorney General’s office failed to even articulate a legal argument for keeping the briefs secret.

So, according to a Court Order of October 15, 2010, counsel for the plaintiffs (Professor Penny Venetis of Rutgers Law School aided by litigators from Patton Boggs LLP) are now free to show you the details of their legal argument.

The briefs are available here:
Plaintiffs’ Proposed Findings of Fact
Plaintiffs’ Proposed Conclusions of Law

I am now free to tell you all sorts of interesting things about my hands-on experiences with (supposedly) tamper-evident security seals. I published some preliminary findings in 2008. Over the next few weeks I’ll post a series of articles about the limitations of tamper-evident seals in securing elections.

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