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A newspaper in Malaysia is reporting on a cell phone cloning scam. The scammer convinces the victim to lend them their cell phone, and the scammer quickly clones it. What’s clever about this scam is that the victim is an Uber driver and the scammer is the passenger, so the driver is naturally busy and can’t see what the scammer is doing.
This is a clever side-channel attack:
The cloning works by using a hot air gun and a scalpel to remove the plastic key casing and expose the NXP A700X chip, which acts as a secure element that stores the cryptographic secrets. Next, an attacker connects the chip to hardware and software that take measurements as the key is being used to authenticate on an existing account. Once the measurement-taking is finished, the attacker seals the chip in a new casing and returns it to the victim.
Extracting and later resealing the chip takes about four hours. It takes another six hours to take measurements for each account the attacker wants to hack. In other words, the process would take 10 hours to clone the key for a single account, 16 hours to clone a key for two accounts, and 22 hours for three accounts.
By observing the local electromagnetic radiations as the chip generates the digital signatures, the researchers exploit a side channel vulnerability in the NXP chip. The exploit allows an attacker to obtain the long-term elliptic curve digital signal algorithm private key designated for a given account. With the crypto key in hand, the attacker can then create her own key, which will work for each account she targeted.
The attack isn’t free, but it’s not expensive either:
A hacker would first have to steal a target’s account password and also gain covert possession of the physical key for as many as 10 hours. The cloning also requires up to $12,000 worth of equipment and custom software, plus an advanced background in electrical engineering and cryptography. That means the key cloning—were it ever to happen in the wild—would likely be done only by a nation-state pursuing its highest-value targets.
That last line about “nation-state pursuing its highest-value targets” is just not true. There are many other situations where this attack is feasible.
Note that the attack isn’t against the Google system specifically. It exploits a side-channel attack in the NXP chip. Which means that other systems are probably vulnerable:
While the researchers performed their attack on the Google Titan, they believe that other hardware that uses the A700X, or chips based on the A700X, may also be vulnerable. If true, that would include Yubico’s YubiKey NEO and several 2FA keys made by Feitian.
Interesting research paper on a bank card chip-and-PIN vulnerability. From the blog post:
Our new paper shows that it is possible to create clone chip cards which normal bank procedures will not be able to distinguish from the real card.
When a Chip and PIN transaction is performed, the terminal requests that the card produces an authentication code for the transaction. Part of this transaction is a number that is supposed to be random, so as to stop an authentication code being generated in advance. However, there are two ways in which the protection can be bypassed: the first requires that the Chip and PIN terminal has a poorly designed random generation (which we have observed in the wild); the second requires that the Chip and PIN terminal or its communications back to the bank can be tampered with (which again, we have observed in the wild).
Interesting research:
Abstract: The HLR/AuC is considered to be one of the most important network elements of a 3G network. It can serve up to five million subscribers and at least one transaction with HLR/AuC is required for every single phone call or data session. This paper presents experimental results and observations that can be exploited to perform a novel distributed denial of service attack in 3G networks that targets the availability of the HLR/AuC. More specifically, first we present an experiment in which we identified and proved some zero-day vulnerabilities of the 3G network that can be exploited by malicious actors to mount various attacks. For the purpose of our experiment, we have used off-the-shelf infrastructure and software, without any specialized modification. Based on the observations of the experiment, we reveal an Advanced Persistent Threat (APT) in 3G networks that aims to flood an HLR/AuC of a mobile operator. We also prove that the discovered APT can be performed in a trivial manner using commodity hardware and software, which is widely and affordably available.
The attack involves cloning SIM cards, then making multiple calls from different handsets in different locations with the same SIM card. This confuses the network into thinking that the same phone is in multiple places at once.
Note that this has not been tested in the field, but there seems no reason why it wouldn’t work.
There’s a lot of insecurity in the fact that cell phones and towers largely trust each other. The NSA and FBI use that fact for eavesdropping, and here it’s used for a denial-of-service attack.
Well, new to us:
You see, an EMV payment card authenticates itself with a MAC of transaction data, for which the freshly generated component is the unpredictable number (UN). If you can predict it, you can record everything you need from momentary access to a chip card to play it back and impersonate the card at a future date and location. You can as good as clone the chip. It’s called a “pre-play” attack. Just like most vulnerabilities we find these days some in industry already knew about it but covered it up; we have indications the crooks know about this too, and we believe it explains a good portion of the unsolved phantom withdrawal cases reported to us for which we had until recently no explanation.
Paper here. And news article.
Clever attack:
When you pay a restaurant bill at your table using a point-of-sale machine, are you sure it’s legit? In the past three months, Toronto and Peel police have discovered many that aren’t.
In what is the latest financial fraud, crooks are using distraction techniques to replace merchants’ machines with their own, police say. At the end of the day, they create another distraction to pull the switch again.
Using information inputted by customers, including PIN data, the criminals are reproducing credit cards at an alarming rate.
Presumably these hacked point-of-sale terminals look and function normally, and additionally save a copy of the credit card information.
Note that this attack works despite any customer-focused security, like chip-and-pin systems.
This article talks about a database of stolen cell phone IDs that will be used to deny service. While I think this is a good idea, I don’t know how much it would deter cell phone theft. As long as there are countries that don’t implement blocking based on the IDs in the databases—and surely there will always be—there will be a market for stolen cell phones.
Plus, think of the possibilities for a denial-of-service attack. Can I report your cell phone as stolen and have it turned off? Surely no political party will think of doing that to the phones of all the leaders of a rival party the weekend before a major election.
Clever attack.
After researching how gift cards work, Zepeda purchased a magnetic card reader online, began stealing blank gift cards, on display for purchase, from Fred Meyer and scanning them with his reader. He would then return some of the scanned cards to the store and wait for a computer program to alert him when the cards were activated and loaded with money.
Using a magnetic card writer, Zepeda then rewrote one of the leftover stolen gift card’s magnetic strip with the activated card’s information, thus creating a cloned card.
ATM skimmers—or fraud devices that criminals attach to cash machines in a bid to steal and ultimately clone customer bank card data—are marketed on a surprisingly large number of open forums and Web sites. For example, ATMbrakers operates a forum that claims to sell or even rent ATM skimmers. Tradekey.com, a place where you can find truly anything for sale, also markets these devices on the cheap.
The truth is that most of these skimmers openly advertised are little more than scams designed to separate clueless crooks from their ill-gotten gains. Start poking around on some of the more exclusive online fraud forums for sellers who have built up a reputation in this business and chances are eventually you will hit upon the real deal.
Generally, these custom-made devices are not cheap, and you won’t find images of them plastered all over the Web.
EDITED TO ADD (6/23): Another post.
It’s easy to clone RFID passports. (To make it clear, the attacker didn’t actually create fake passports; he just stole the data off the RFID chips.) Not that this hasn’t been done before.
I’ve long been opposed to RFID chips in passports, and have written op eds about them in the International Herald Tribune and several other papers.
EDITED TO ADD (2/11): I got some details wrong. Chris Paget, the researcher, is cloning Western Hemisphere Travel Initiative (WHTI) compliant documents such as the passport card and Electronic Drivers License (EDL), and not the passport itself. Here is the link to Paget’s talk at ShmooCon.
Sidebar photo of Bruce Schneier by Joe MacInnis.