Liudvikas Bukys

Yesterday I reported to my local Hall of Justice for jury duty.

They offer free wireless for jurors waiting to be called into the court. In the vicinity was the state-run access point, and a host-to-host wireless network calling itself “Free Internet Service”.

What could that be but a man-in-the-middle attacker interested in packet capture? It could have been one of the other jurors. Or a box somebody placed deliberately close to the known public access point.

Due to security fatigue I didn’t even try to gather any information on the rogue. Now my conscience is catching up to me, telling me I should at least tell the Hall of Justice folks, in case this MITM is a permanent installation.

I’ve been helping to organize a regional security conference, the second annual Rochester Security Summit, scheduled for October 3 and 4. Good presenters, both business and technical tracks. Some seats are still open, register now!

Local Rochester-area political blogger Thomas Belknap recently railed about HR 811, interpreting its requirement of a voter-verified durable paper ballot as a small-minded banning of an attractive future of modern networked reliable electronic voting machines. I could not resist posting my disagreement into the comments on his blog, and perhaps I am going to convince him, as he edited out my most provocative snide political shots and left in some of my more reasoned comments.

As a security person, I must point out that if machines do not produce a reliable auditable record, then all you have is a fait accompli fraud-blessing device. That’s the short version of the security argument.

I’m willing to go along with NIST that, as of today, all-electronic systems are an important research topic, not a settled present alternative:

The approach to software-independence used in op scan is based on voter-verified paper records, but some all-electronic paperless approaches have been proposed. It is a research topic currently as to whether software independence may be able to be accomplished via systems that would produce an all-electronic voter-verified, independent audit trail (known as software IV systems).

A durable paper ballot requirement is not a retrograde goof, nor a rejection of e-voting. It’s a reflection of current reality, that all-electronic e-voting implementations are asking for trouble. Codifying an allowance for all-electronic systems today would just open the door to arguments about what’s good enough cryptographically, arguments that will be settled by folks even less competent than our representatives. Codifying the well-understood voter-verified paper audit trail as a requirement puts an immediate crimp in the shopping spree for fancy-looking machines that are rotten inside - a shopping spree that will continue if this law isn’t passed, creating an ever-larger lump of sunk investment in pretty bad technology.

A paper audit trail today isn’t a rejection of e-voting, it is progress toward a more robust implementation that in the future will, no doubt, also include other alternative durable auditable records.

For credible background on the security geek consensus, see the above-quoted NIST draft, the US ACM policy recommendation, or Bruce Schneier (University of Rochester physics alumnus!). Or anything by Ed Felten or Avi Rubin on this subject. In this case, our representatives seem to be listening to informed advisers.

Regarding politics: All parties’ oxes have been gored at one time or another by voting fraud or rumors of fraud, so this does seem like an issue on which a consensus could form.

My installation of Microsoft Internet Explorer 6 (version 6.0.2900.2180.xpsp_sp2_gdr.050301-1519) has developed the unfortunate problem of frequently (about once a day) trashing its ability to render correctly: painting its window contents at various places all over the display, rendering in the wrong font, leaving turds all over its window while scrolling. Once it starts I have to kill iexplore.exe to make it stop. I believe it is fully-patched.

In my mind the appearance of this problem is correlated with the appearance of two new aggressive JavaScript interfaces: The much-improved BlogLines feed selector, and the very-irritating Yahoo Finance streaming quotes feature (which slows down every refresh even when set to “off”). That may just be coincidence.

It does mean there’s some serious undiscovered memory corruption going inside IE6 somewhere.

It’s a good time to switch to FireFox and/or IE7.

Yahoo’s release of open access to its BBAuth authentication service (see also here and here) is a big step forward. It’s just the thing for many simple applications. It’s not as good as a user-controlled cross-provider identity scheme, but the emergence of a few real high-volume competing web services will help drive us there.

The New York State School Tax Relief (STAR) program is an identity theft “accident” waiting to happen. Homeowners apply for property exemptions on their primary residence, and file with their local tax assessors. (In the first year or so of this program, total chaos ensued in assessor’s offices all over the state.) Extra tax exemptions for senior citizens are means-tested, and require homeowners to submit their SSN or a copy of their income tax returns to the local assessor.

• In New York City, they want SSNs from everybody. Just because it’s authorized by law (in the NYC Administrative Code) doesn’t mean it’s a good idea. Everywhere else, they’re only collecting SSNs or income tax returns from low-income seniors.
• It’s hard to justify leaving so much personal financial information sloshing around assessor’s offices all over the state. And which is worse: copies of tax returns in piles in sleepy small-town assessor’s messy offices, or huge indifferent big-city assessor’s chaotic offices? Need to know? Mind your own business.
• As their normal traffic is public information, assessors are not necessarily tuned to protecting private personal information. For a recent example of a public record agency handling private data, see the story of how the Suffolk County (NY) clerk’s normal processes put a few thousand SSN’s in the public record [via Emergent Chaos].
• Perhaps all these violations of “don’t ask for information you don’t need” and “don’t store information you don’t need again” were less serious even a few years ago, but the consequences of these old ways are getting worse every day.
• Though it’s hard to patch the process perfectly, one simple fix would be to direct the flow of sensitive information away from local offices, e.g. create a state tax return checkoff that allows the income tax people to inform the assessors about eligibility and primary residence status without revealing any income information.
• Well, the politics is irritating too. Creating yet another “take with one hand, give back with another” program is inefficient, and clearly its primary purpose is to create an opportunity for attaching a politician’s name to a tax cut, with extra discrimination making the program harder to kill.

Update 3/7/2006 see also: The public servants at the Ohio secretary of state insist on treating documents that pass through their hands as public despite embedded SSNs.

Update 4/11/2006 see also: Broward County (FL).

Michal Zalewski identifies a new class of attacks, that he dubs Cross Site Cooking:

There are three fairly interesting flaws in how HTTP cookies were designed and later implemented in various browsers; these shortcomings make it possible (and alarmingly easy) for malicious sites to plant spoofed cookies that will be relayed by unsuspecting visitors to legitimate, third-party servers.

While a well-coded web application should be designed to resist attacks from hostile HTTP clients, these new attacks turn every browser into a hostile HTTP client, and it’s a good bet that many web applications are hanging on a pretty thin thread of “this can’t happen” assumptions, soon to be violated. Expect a large number of embarrassing vulnerability reports to ensue.

[via http://del.icio.us/emergentchaos/new.attack.class%3F]

I am enjoying the series of articles on business growth and fraud at the Financial Cryptography web site. The overall theme is that, whatever level of technical perfection you achieve in a money-handling system, things really only get interesting once the business takes off — at which point an equilibrium is reached based both on what you implemented and on how much it’s worth attacking. The first article started the series a bit slow and abstract; for me, I like details. The latest installment, the most concrete so far, is a case study regarding e-Gold, with some bonus comments regarding WebMoney. Note that even without technical flaws, your business is still affected by attacks on the whole business ecology (much of it out of your direct control): partners, customers, complementary businesses, reputation mongers.

Ed Felten discusses an interesting dispute among astronomers regarding how long scholars should withhold discoveries so they can retain exclusive access and get credit for more original papers. (Aside: As I note in his comments, while this is largely self-governing because everybody has incentives to publish, there are occasional extreme examples of scholarly hoarding, such as the decades-long embargo on publication of some Dead Sea Scroll materials.)

The security angle on this is that the dispute is about whether the Spaniards scooped the Americans by reverse-engineering a temporary name published in an advance abstract of a paper. The temporary name contained a date that could have served as an index into a telescope activity log, revealing the position of the newly-discovered object.

The lesson is that a cookies or nonces (temporary data values to be used only once) should usually, in security applications, be content-free (long, random, unpredictable, and generated with a random number generator not prone to reverse engineering itself). Structured or predictable nonces can lead to information leaks or to vulnerability to forgery. Short nonces fall to brute-force search.

Kumar, Paxson, Weaver: “Outwitting the Witty Worm: Exploiting Underlying Structure for Detailed Reconstruction of an Internet Scale Event” is a brilliant forensic analysis. Their overview:

Many Internet worms use pseudo-random numbers to scan the IP address-space. In this project, we reverse engineered the state of the pseudo-random number generator (pRNG) which the Witty worm used to generate packets. By combining our knowledge of Witty’s code with the pRNG state, we performed a detailed recreation of the worm’s spread. We were able to discover several characteristics of the infected systems, including their uptime, network access bandwidth, and number of disks. Additionally, we were able to find specific details about the worm author’s deliberate targeting of a US Military base, and determine the identity of Patient 0, the system used to launch the worm.

and there’s interesting followon discussion at SecurityFocus.