February 24, 2018

Transit Card Maker Sues Dutch University to Block Paper

NXP, which makes the Mifare transit cards used in several countries, has sued Radboud University Nijmegen (in the Netherlands), to block publication of a research paper, “A Practical Attack on the MIFARE Classic,” that is scheduled for publication at the ESORICS security conference in October. The new paper reportedly shows fatal security flaws in NXP’s Mifare Classic, which appears to be the world’s most commonly used contactless smartcard.

I wrote back in January about the flaws found by previous studies of Mifare. After the previous studies, there wasn’t much left to attack in Mifare Classic. The new paper, if its claims are correct, shows that it’s fairly easy to defeat MIFARE Classic completely.

It’s not clear what legal argument NXP is giving for trying to suppress the paper. There was a court hearing last week in Arnheim, but I haven’t seen any reports in the English-language press. Perhaps a Dutch-speaking reader can fill in more details. An NXP spokesman has called the paper “irresponsible” but that assertion is hardly a legal justification for censoring the paper.

Predictably, a document purporting to be the censored paper showed up on Wikileaks, and BoingBoing linked to it. Then, for some reason, it disappeared from Wikileaks, though BoingBoing commenters quickly pointed out that it was still available in Google’s cache of Wikileaks, and also at Cryptome. But why go to a leak-site? The same article has been available on the Web all along at arxiv, a popular repository of sci/tech research preprints run by the Cornell University library.

[UPDATE (July 15): It appears that Wikileaks had the wrong paper, though one that came from the same Radboud group. The censored paper is called “Dismantling Mifare Classic”.]

As usual in these cases of censorship-by-lawsuit, it’s hard to see what NXP is trying to achieve with the suit. The research is already done and peer-reviewed,. The suit will only broaden the paper’s readership. NXP’s approach will alienate the research community. The previous Radboud paper already criticizes NXP’s approach, in a paragraph written before the lawsuit:

We would like to stress that we notified NXP of our findings before publishing our results. Moreover, we gave them the opportunity to discuss with us how to publish our results without damaging their (and their customers) immediate interests. They did not take advantage of this offer.

What is really puzzling here is that the paper is not a huge advance over what has already been published. People following the literature on Mifare Classic – a larger group, thanks to the lawsuit – already know that the system is unsound. Had NXP reacted responsibly to this previous work, admitting the Mifare Classic problems and getting to work on migrating customers to newer, more secure products, none of this would have been necessary.

You’ve got to wonder what NXP was thinking. The lawsuit is almost certain to backfire: it will only boost the audience of the censored paper and of other papers criticizing Mifare Classic. Perhaps some executive got angry and wanted to sue the university out of spite. Things can’t be comfortable in the executive suite: NXP’s failure to get in front of the Mifare Classic problems will (rightly) erode customers’ trust in the company and its products.

UPDATE (July 18): The court ruled against NXP, so the researchers are free to publish. See Mrten’s comment below.

NJ Voting Machine Tape Shows Phantom Obama Vote

I’ve written before (1, 2, 3) about discrepancies in the election results from New Jersey’s February 5 presidential primary. Yesterday we received yet another set of voting machine result tapes. They show a new kind of discrepancy which we haven’t seen before – and which contradicts the story told by Sequoia (the vendor) and the NJ Secretary of State about what went wrong in the election.

The new records are from three voting machines in Pennsauken, District 6. We have the result tapes printed out by all three voting machines in that district (1, 2, 3). As usual, each result tape has a “Candidate Totals” section giving the vote count for each candidate, and a separate “Option Switch Totals” section giving the voter turnout in each party. We also have the Democratic vote totals reported by the county clerk for that district (and some others), which were apparently calculated from the memory cartridges used in the three machines.

The county clerk’s totals show 279 votes in Pennsauken District 6. The per-candidate counts are Clinton 181, Obama 94, Richardson 2, Edwards 1, Kucinich 0, Biden 1, which adds up correctly to 279. The turnout sections of the three result tapes also show a total Democratic turnout of 279 (133+126+20).

But the Candidate Totals sections of the tapes tell a different story. Adding up the three tapes, the totals are Clinton 181, Obama 95, Richardson 2, Edwards 1, Kucinich 0, Biden 1, which adds up to 280. The Candidate Totals on the tapes show an extra Obama vote that doesn’t appear anywhere else.

(Everything seems to add up on the Republican side.)

The State claimed, in response to some (but not all) of the discrepancies I pointed out previously, that I had misread the tapes. This time the tapes are absolutely clear. Here are the Democratic candidate totals from the three tapes:

Here are the turnout sections of the three tapes:

(These images are all scans – the original documents Camden County sent me are even clearer.)

This is wrong. It is inconsistent with Sequoia’s explanation for the previously-noticed discrepancies. It is inconsistent with the State’s theory of what went wrong in the election.

It’s time for an independent investigation.

Sequoia's Explanation, and Why It's Not the Whole Story

I wrote yesterday about discrepancies in the results reported by Sequoia AVC Advantage voting machines in New Jersey.

Sequoia issued a memo giving their explanation for what might have happened. Here’s the relevant part:

During a primary election, the “option switches” on the operator panel must be used to activate the voting machine. The operator panel has a total of 12 buttons numbered 1 through 12. Each party participating in the primary election is assigned one of the option switch buttons. The poll worker presses a party option switch button based on the voter authorization slip given to the voter after signing the poll book, and then the poll worker presses the green “Activate” button. This action causes that party’s contests to be activated on the ballot face inside the voting booth.

Let’s assume the Democrat party is assigned option switch 6 while the Republican Party is assigned options switch 12. If a Democrat voter arrives, the poll worker presses the “6” button followed by the green “Activate” button. The Democrat contests are activated and the voter votes the ballot. For a Republican voter, the poll worker presses the “12” button followed by the green “Activate” button, which then activates the Republican contests and the voter votes the ballot. This is the correct and proper method of machine activation when using option switches.

However, we have found that when a poll worker selects the lower of the two assigned selection codes, followed by pressing an unused selection code and then pressing the green “Activate” button, the higher numbered party on the operator panel has its contests activated instead while the selection code button for the original party stays active on the operator panel.

Using the above example with the Democrat Party as option switch 6 and the Republican Party as option switch 12, the poll worker presses button 6 for Democrat. The red light next to button number 6 lights up and the operator panel display will show DEM. The poll worker then presses any unused option switch. The red light stays lit next to option switch 6 and the display still says DEM. Now the poll worker presses the green “Activate” button. The red light stays lit next to button number 6, but the operator panel display now says REP and the ballot in the voting booth will activate the Republican party contests.

In each and every case where a machine displays the party turnout issue at the close of the polls, this is the situation that would have caused it, and it can be duplicated on any machine. In addition, for this situation to have occurred, the voter that was in the voting booth at the time of the poll workers action would have voted the opposite party ballot instead of telling the poll worker that the incorrect ballot was activated and the machine would not allow them to vote the party they intended. If they had informed the poll worker, they could have made the party selection change and the voter would have then voted the correct ballot style.

Several points are in order.

First, it’s obvious from this description, and from the fact that this happened on so many machines across the state, that even if Sequoia’s explanation is entirely correct, there was some kind of engineering error on Sequoia’s part that caused the machines to misbehave. Sequoia has tried to paint the anomalies as poll worker error, but that’s not plausible in light of Sequoia’s own explanation.

Consider the scenario described above: there is a moment when the red light next to the DEM button is lit, the operator panel displays DEM, then the poll worker presses the Activate button – and the Republican ballot is activated. No competent engineer would design a system to work that way.

No competent engineer would design this system to ever display REP in the operator panel while simultaneously lighting only the DEM light.

No competent engineer would design this system to ever activate the Republican ballot when the poll worker had pressed the DEM button but had not pressed the REP button.

Sequoia’s own explanation makes clear that they made an engineering error that caused the voting machine to behave incorrectly.

Second, this doesn’t look like fraud, only error. A malicious attacker who had access to a machine would have had much more powerful, and much less detectable, options at his disposal.

Third, Sequoia seems to avoid saying that what they describe is the only possible cause of such errors. Note the careful wording, “In each and every case where a machine displays [an error], this is the situation that would have caused it …” (emphasis added). They don’t say this “did” cause the errors; they say it “would have”. The sentence is either clumsy or artfully worded.

Fourth, Sequoia’s explanation involves a voter seeing the wrong party’s ballot being activated, and not complaining about it. Assuming (as press accounts say) that the problem happened about sixty times in New Jersey, one would expect that many voters noticed and complained. And one would expect that in at least one of those cases, a poll worker would have noticed that the operator panel was displaying REP and DEM at the same time. Yet there don’t seem to be reports of such behavior.

Fifth, Sequoia doesn’t characterize fully the cases where this problem might occur, so election officials don’t know, for example, which past elections might have been affected.

The bottom line is clear. An investigation is needed – an independent investigation, done by someone not chosen by Sequoia, not paid by Sequoia, and not reporting to Sequoia.