Posts tagged ‘identity stealing’

One Click Frauds and Identity Leakage: Two Trends on a Collision Course

One of my favorite computer security papers of 2010 is by Nicolas Christin, Sally Yanagihara and Keisuke Kamataki on “one click frauds,” a simple yet shockingly effective form of social engineering endemic to Japan. I will let the authors explain:

In the family apartment in Tokyo, Ken is sitting at his computer, casually browsing the free section of a mildly erotic website. Suddenly, a window pops up, telling him,

Thank you for your patronage! You successfully registered for our premium online services, at an incredible price of 50,000 JPY. Please promptly send your payment by bank transfer to ABC Ltd at Ginko Bank, Account 1234567. Questions? Please contact us at 080-1234-1234.

Your IP address is, you run Firefox 3.5 over Windows XP, and you are connecting from Tokyo.

Failure to send your payment promptly will force us to mail you a postcard reminder to your home address. Customers refusing to pay will be prosecuted to the fullest extent of the law. Once again, thank you for your patronage!

A sample postcard reminder is shown on the screen, and consists of a scantily clad woman in a provocative pose. Ken has a sudden panic attack: He is married, and, if his wife were to find out about his browsing habits, his marriage would be in trouble, possibly ending in divorce, and public shame. In his frenzied state of mind, Ken also fears that, if anybody at his company heard about this, he could possibly lose his job. Obviously, those website operators know who he is and where he lives, and could make his life very difficult. Now, 50,000 JPY (USD 500) seems like a small price to pay to make all of this go away. Ken immediately jots down the contact information, goes to the nearest bank, and acquits himself of his supposed debt.

Ken has just been the victim of a relatively common online scam perpetrated in Japan, called “One Click Fraud.” In this fraud, the “customer,” i.e., the victim, does not enter any legally binding agreement, and the perpetrators only have marginal information about the client that connected to their website (IP address, User-Agent string), which does not reveal much about the user. However, facing a display of authority stressed by the language used, including the notion that they are monitored, and a sense of shame from browsing sites with questionable contents, most victims do not realize they are part of an extortion scam. Some victims even call up the phone numbers provided, and, in hopes of resolving the situation, disclose private information, such as name or address, to their tormentors, which makes them even more vulnerable to blackmail.

As a result, One Click Frauds have been very successful in Japan. Annual police reports show that the estimated amount of monetary damages stemming from One Click Frauds and related confidence scams are roughly 26 billion JPY per year (i.e., USD 260 million/year). [emphasis mine]

The authors offer a fascinating economic analysis based on a near-exhaustive collection of fraud reports over a several-year period. Each scam offers 3 types of data points: the domain name where the scam appeared, the phone number the victim is asked to call, and the bank account number where the money is asked to be deposited. They plot the graph of all links between the ~500 domains, ~700 bank accounts and ~200 phone numbers, and report, among other nifty findings, that at most 13 groups are responsible for over half of all one-click frauds. Based on simple cost estimates, they also find that for each scam operated, the scammers recover their costs (bank account fee, bandwidth, etc.) with as few as 4 victims per year.

In this post I want to talk about the possible evolution of one-click frauds. At some point, either due to public awareness campaigns or due to saturation, the Japanese public will catch on to the fact that the attempted blackmail is fake and that the websites don’t actually have their identity. When this happens the scammers will be forced to up their game. Another impetus for increasing sophistication is making the fraud work outside Japan—the current version probably won’t work; the instinctive obedience of apparent authority seems characteristically Japanese.

And by ‘up their game,’ I mean that the scammers will probably get wise to the fact that they can discover the victim’s actual identity, and establish a credible threat instead of a fake one.

Readers of this blog know that I have announced or reported numerous attacks/vulnerabilities under the “ubercookies” series (1, 2, 3, 4, and part of 5) that allow a website to uncover a visitor’s identity, i.e., a Google/Facebook/Twitter handle. At the same time, connecting an online profile or email address to real-world information is becoming increasingly easy to automate. Putting two and two together, it is clear why one-click frauds could get very serious any day.

What might stop this logical progression of one-click frauds? Perhaps all identity-leak vulnerabilities will be found and fixed, but that’s a rather naïve hope, as the history of malware shows. Or maybe the public will eventually learn to resist the scam even in the face of a credible threat. That will take a long time, however, and a lot of damage will be done by then. Perhaps the technical skills required will remain beyond the reach of the scammers. But experience suggests that with a sufficiently lucrative prize, technical sophistication is no barrier—all it takes is one or two actual hackers; script-kiddie scammers can take care of the rest.

The best hope, as with any scam, is law enforcement. The authors list several factors, many specific to Japan, why the prosecution probability for one-click frauds is currently low. In addition, penalties for those who do get caught are also low: “One Click Frauds very often do not meet the legal tests necessary for qualifying as “fraud,” as in the vast majority of cases, the victim pays up immediately, and there is no active blackmailing effort from the miscreant.” A version of the scam that involved identity stealing would likely fall under the US Computer Fraud and Abuse Act or an equivalent, and would thus be more clearly illegal. Will this make a difference? Let’s wait and see.

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February 21, 2011 at 5:30 pm 2 comments

Yet Another Identity Stealing Bug. Will Creeping Normalcy be the Result?

Elie Bursztein points me to a “Cross Site URL Hijacking” attack which, among other things, allows a website to identify a visitor instantly (if they are using Firefox) by finding their Google and possibly Facebook IDs. Here is a live demo and here’s a paper.

For the security geeks, the attack works by exploiting a Firefox bug that allows a page in the attacker domain to infer URLs of pages in the target domain. If a page like redirects to[username] (which is quite common), the attacker can learn the username by requesting the page in a script tag.

Let us put this attack in context. Stealing the identity of a web visitor should be familiar to readers of this blog. I’ve recently written about doing this via history stealing, then a bug in Google spreadsheets, and now we have this. While the spreadsheets bug was fixed, the history stealing vulnerability remains in most browsers. Will new bugs be found faster than existing ones getting fixed? The answer is probably yes.

Something that is of much more concern in the long run is Facebook’s instant personalization, which is basically like identity stealing, except it is a feature rather than a bug. Currently Facebook identities are available without user consent to only 3 partners (Yelp, Pandora and but there will be inevitable competitive pressures both for Facebook to open this up to more websites as well as for other identity providers to offer a similar service.

Legitimate methods and hacks based on bugs are not entirely distinct. Two XSS attacks on were found in quick succession either of which could have been exploited by a third (fourth?) party for identity stealing. Instant personalization (and similar attempts at an “identity layer”) greatly increase the chance of bugs that leak your identity to every website, authorized or not.

As identity-stealing bugs as well as identity-sharing features proliferate, the result is going to be creeping normalcy — users will get slowly inured to the idea that any website they visit might have their identity. And that will be a profound change for the way the web works. Of course, savvy users will know how to turn off the various tracking mechanisms, but most people will be left in the lurch.

We are still at the early stages of this shift. It is clear that it will have both good and ill effects. For example, people are much more civil when interacting under their real-life identity. For this reason, there is quite a clamor for identity. For instance, see News Sites Rethink Anonymous Online Comments and The Forces Align Against Anonymity. But like every change, this one is going to be hard to get used to.

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June 1, 2010 at 9:38 am 2 comments


I’m an associate professor of computer science at Princeton. I research (and teach) information privacy and security, and moonlight in technology policy.

This is a blog about my research on breaking data anonymization, and more broadly about information privacy, law and policy.

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