All About Skimmers


2
Nov 18

SMS Phishing + Cardless ATM = Profit

Thieves are combining SMS-based phishing attacks with new “cardless” ATMs to rapidly convert phished bank account credentials into cash. Recent arrests in Ohio shed light on how this scam works.

A number of financial institutions are now offering cardless ATM transactions that allow customers to withdraw cash using nothing more than their mobile phones. But this also creates an avenue of fraud for bad guys, who can leverage phished or stolen account credentials to add a new phone number to the customer’s account and then use that added device to siphon cash from hijacked accounts at cardless ATMs.

Image: Mastercard.us

In May 2018, Cincinnati, Ohio-based financial institution Fifth Third Bank began hearing complaints from customers who were receiving text messages on their phones that claimed to be from the bank, warning recipients that their accounts had been locked.

The text messages contained a link to unlock their accounts and led customers to a Web site that mimicked the legitimate Fifth Third site. That phishing site prompted visitors to enter their account credentials — including usernames, passwords, one-time passcodes and PIN numbers — to unlock their accounts.

All told, that scam netted credentials for approximately 125 Fifth Third customers — most of them in or around the Cincinnati area. The crooks then used the phished data to withdraw $68,000 from 17 ATMs in Illinois, Michigan, and Ohio in less than two weeks using Fifth Third’s cardless ATM function.

According to court documents, the SMS phishing and fraudulent withdrawals at cardless ATMs continued through October 2018, earning the scammers an additional $40,000. That is, until the bank zeroed in on four individuals suspected of perpetrating the crime spree. Shortly thereafter, four men were arrested in connection with the crimes. Continue reading →


27
Sep 18

Secret Service Warns of Surge in ATM ‘Wiretapping’ Attacks

The U.S. Secret Service is warning financial institutions about a recent uptick in a form of ATM skimming that involves cutting cupcake-sized holes in a cash machine and then using a combination of magnets and medical devices to siphon customer account data directly from the card reader inside the ATM.

According to a non-public alert distributed to banks this week and shared with KrebsOnSecurity by a financial industry source, the Secret Service has received multiple reports about a complex form of skimming that often takes thieves days to implement.

This type of attack, sometimes called ATM “wiretapping” or “eavesdropping,” starts when thieves use a drill to make a relatively large hole in the front of a cash machine. The hole is then concealed by a metal faceplate, or perhaps a decal featuring the bank’s logo or boilerplate instructions on how to use the ATM.

A thin metal faceplate is often used to conceal the hole drilled into the front of the ATM. The PIN pad shield pictured here is equipped with a hidden spy camera.

Skimmer thieves will fish the card skimming device through the hole and attach it to the internal card reader via a magnet.

Thieves often use a magnet to secure their card skimmer in place above the ATM’s internal card reader. Image: U.S. Secret Service.

Very often the fraudsters will be assisted in the skimmer installation by an endoscope, a slender, flexible instrument traditionally used in medicine to give physicians a look inside the human body. By connecting a USB-based endoscope to his smart phone, the intruder can then peek inside the ATM and ensure that his skimmer is correctly attached to the card reader. Continue reading →


26
Jun 18

How to Avoid Card Skimmers at the Pump

Previous stories here on the proliferation of card-skimming devices hidden inside fuel pumps have offered a multitude of security tips for readers looking to minimize their chances of becoming the next victim, such as favoring filling stations that use security cameras and tamper-evident tape on their pumps. But according to police in San Antonio, Texas, there are far more reliable ways to avoid getting skimmed at a fuel station.

San Antonio, like most major U.S. cities, is grappling with a surge in pump skimming scams. So far in 2018, the San Antonio Police Department (SAPD) has found more than 100 skimming devices in area fuel pumps, and that figure already eclipses the total number of skimmers found in the area in 2017. The skimmers are hidden inside of the pumps, and there are often few if any outward signs that a pump has been compromised.

In virtually all cases investigated by the SAPD, the incidents occurred at filling stations using older-model pumps that have not yet been upgraded with physical and digital security features which make it far more difficult for skimmer thieves to tamper with fuel pumps and siphon customer card data (and PINs from debit card users).

Lt. Marcus Booth is the financial crimes unit director for the SAPD. Booth said most filling stations in San Antonio and elsewhere use legacy pumps that have a vertical card reader and a flat, membrane-based keypad. In addition, access to the insides of these older pumps frequently is secured via a master key that opens not only all pumps at a given station, but in many cases all pumps of a given model made by the same manufacturer.

Older model fuel pumps like this one feature a flat, membrane-based keypad and vertical card reader. Image: SAPD.

In contrast, Booth said, newer and more secure pumps typically feature a horizontal card acceptance slot along with a raised metallic keypad — much like a traditional payphone keypad and referred to in the fuel industry as a “full travel” keypad:

Newer, more tamper-resistant fuel pumps include raised metallic keypads (known in the industry as “full travel” keypads), horizontal card readers and custom locks for each pump.

Booth said the SAPD has yet to see a skimming incident involving newer pump models like the one pictured directly above.

“Here in San Antonio, many of these stations with these older keypads and card slots were getting hit all the time, sometimes weekly,” he said. “But as soon as those went over to newer gear, we’ve seen zero problems.”

According to Booth, the newer pumps include not only custom keys for each pump, but also tamper protections that physically shut down a pump if the machine is improperly accessed. What’s more, these more advanced pumps do a better job of compartmentalizing individual components, very often enclosing the electronics that serve the card reader and keypad in separately secured metal cages.

“Pretty much all these full travel metallic keypads are encrypted, and if you disconnect them they disable themselves and can only be re-enabled by technician,” Booth told KrebsOnSecurity. “Also, if the pump is opened improperly, it disables itself. These two specific items: The card reader or the pad, if you pull power to them they’re dead, and then they can only be re-enabled by an authorized technician.”

Newer pumps may also include more modern mobile payment options — such as Apple Pay — although many stations with pumps that advertise this capability have not yet enabled it, which allows customers to pay for fuel without ever sharing their credit or debit card account details with the fuel station. Continue reading →


14
May 18

Detecting Cloned Cards at the ATM, Register

Much of the fraud involving counterfeit credit, ATM debit and retail gift cards relies on the ability of thieves to use cheap, widely available hardware to encode stolen data onto any card’s magnetic stripe. But new research suggests retailers and ATM operators could reliably detect counterfeit cards using a simple technology that flags cards which appear to have been altered by such tools.

A gift card purchased at retail with an unmasked PIN hidden behind a paper sleeve. Such PINs can be easily copied by an adversary, who waits until the card is purchased to steal the card’s funds. Image: University of Florida.

Researchers at the University of Florida found that account data encoded on legitimate cards is invariably written using quality-controlled, automated facilities that tend to imprint the information in uniform, consistent patterns.

Cloned cards, however, usually are created by hand with inexpensive encoding machines, and as a result feature far more variance or “jitter” in the placement of digital bits on the card’s stripe.

Gift cards can be extremely profitable and brand-building for retailers, but gift card fraud creates a very negative shopping experience for consumers and a costly conundrum for retailers. The FBI estimates that while gift card fraud makes up a small percentage of overall gift card sales and use, approximately $130 billion worth of gift cards are sold each year.

One of the most common forms of gift card fraud involves thieves tampering with cards inside the retailer’s store — before the cards are purchased by legitimate customers. Using a handheld card reader, crooks will swipe the stripe to record the card’s serial number and other data needed to duplicate the card.

If there is a PIN on the gift card packaging, the thieves record that as well. In many cases, the PIN is obscured by a scratch-off decal, but gift card thieves can easily scratch those off and then replace the material with identical or similar decals that are sold very cheaply by the roll online.

“They can buy big rolls of that online for almost nothing,” said Patrick Traynor, an associate professor of computer science at the University of Florida. “Retailers we’ve worked with have told us they’ve gone to their gift card racks and found tons of this scratch-off stuff on the ground near the racks.”

At this point the cards are still worthless because they haven’t yet been activated. But armed with the card’s serial number and PIN, thieves can simply monitor the gift card account at the retailer’s online portal and wait until the cards are paid for and activated at the checkout register by an unwitting shopper.

Once a card is activated, thieves can encode that card’s data onto any card with a magnetic stripe and use that counterfeit to purchase merchandise at the retailer. The stolen goods typically are then sold online or on the street. Meanwhile, the person who bought the card (or the person who received it as a gift) finds the card is drained of funds when they eventually get around to using it at a retail store.

The top two gift cards show signs that someone previously peeled back the protective sticker covering the redemption code. Image: Flint Gatrell.

Traynor and a team of five other University of Florida researchers partnered with retail giant WalMart to test their technology, which Traynor said can be easily and quite cheaply incorporated into point-of-sale systems at retail store cash registers. They said the WalMart trial demonstrated that researchers’ technology distinguished legitimate gift cards from clones with up to 99.3 percent accuracy.

While impressive, that rate still means the technology could still generate a “false positive” — erroneously flagging a legitimate customer as using a fraudulently obtained gift card in a non-trivial number of cases. But Traynor said the retailers they spoke with in testing their equipment all indicated they would welcome any additional tools to curb the incidence of gift card fraud.

“We’ve talked with quite a few retail loss prevention folks,” he said. “Most said even if they can simply flag the transaction and make a note of the person [presenting the cloned card] that this would be a win for them. Often, putting someone on notice that loss prevention is watching is enough to make them stop — at least at that store. From our discussions with a few big-box retailers, this kind of fraud is probably their newest big concern, although they don’t talk much about it publicly. If the attacker does any better than simply cloning the card to a blank white card, they’re pretty much powerless to stop the attack, and that’s a pretty consistent story behind closed doors.” Continue reading →


6
Feb 18

Would You Have Spotted This Skimmer?

When you realize how easy it is for thieves to compromise an ATM or credit card terminal with skimming devices, it’s difficult not to inspect or even pull on these machines when you’re forced to use them personally — half expecting something will come detached. For those unfamiliar with the stealth of these skimming devices and the thieves who install them, read on.

Police in Lower Pottsgrove, PA are searching for a pair of men who’ve spent the last few months installing card and PIN skimmers at checkout lanes inside of Aldi supermarkets in the region. These are “overlay” skimmers, in that they’re designed to be installed in the blink of an eye just by placing them over top of the customer-facing card terminal.

The top of the overlay skimmer models removed from several Aldi grocery story locations in Pennsylvania over the past few months.

The underside of the skimmer hides the brains of this little beauty, which is configured to capture the personal identification number (PIN) of shoppers who pay for their purchases with a debit card. This likely describes a great number of loyal customers at Aldi; the discount grocery chain only in 2016 started accepting credit cards, and previously only took cash, debit cards, SNAP, and EBT cards.

The underside of this skimmer found at Aldi is designed to record PINs.

The Lower Pottsgrove police have been asking local citizens for help in identifying the men spotted on surveillance cameras installing the skimming devices, noting that multiple victims have seen their checking accounts cleaned out after paying at compromised checkout lanes.

Local police released the following video footage showing one of the suspects installing an overlay skimmer exactly like the one pictured above. The man is clearly nervous and fidgety with his feet, but the cashier can’t see his little dance and certainly doesn’t notice the half second or so that it takes him to slip the skimming device over top of the payment terminal.

Continue reading →


30
Jan 18

Drugs Tripped Up Suspects In First Known ATM “Jackpotting” Attacks in the US

On Jan. 27, 2018, KrebsOnSecurity published what this author thought was a scoop about the first known incidence of U.S. ATMs being hit with “jackpotting” attacks, a crime in which thieves deploy malware that forces cash machines to spit out money like a loose Las Vegas slot machine. As it happens, the first known jackpotting attacks in the United States were reported in November 2017 by local media on the west coast, although the reporters in those cases seem to have completely buried the lede.

Isaac Rafael Jorge Romero, Jose Alejandro Osorio Echegaray, and Elio Moren Gozalez have been charged with carrying out ATM “jackpotting” attacks that force ATMs to spit out cash like a Las Vegas casino.

On Nov. 20, 2017, Oil City News — a community publication in Wyoming — reported on the arrest of three Venezuelan nationals who were busted on charges of marijuana possession after being stopped by police.

After pulling over the van the men were driving, police on the scene reportedly detected the unmistakable aroma of pot smoke wafting from the vehicle. When the cops searched the van, they discovered small amounts of pot, THC edible gummy candies, and several backpacks full of cash.

FBI agents had already been looking for the men, who were allegedly caught on surveillance footage tinkering with cash machines in Wyoming, Colorado and Utah, shortly before those ATMs were relieved of tens of thousands of dollars.

According to a complaint filed in the U.S. District Court for the District of Colorado, the men first hit an ATM at a credit union in Parker, Colo. on October 10, 2017. The robbery occurred after business hours, but the cash machine in question was located in a vestibule available to customers 24/7.

The complaint says surveillance videos showed the men opening the top of the ATM, which housed the computer and hard drive for the ATM — but not the secured vault where the cash was stored. The video showed the subjects reaching into the ATM, and then closing it and exiting the vestibule. On the video, one of the subjects appears to be carrying an object consistent with the size and appearance of the hard drive from the ATM.

Approximately ten minutes later, the subjects returned and opened up the cash machine again. Then they closed the top of the ATM and appeared to wait while the ATM computer restarted. After that, both subjects could be seen on the video using their mobile phones. One of the subjects reportedly appeared to be holding a small wireless mini-computer keyboard.

Soon after, the ATM began spitting out cash, netting the thieves more than $24,000. When they they were done, the suspects allegedly retrieved their equipment from the ATM and left.

Forensic analysis of the ATM hard drive determined that the thieves installed the Ploutus.D malware on the cash machine’s hard drive. Ploutus.D is an advanced malware strain that lets crooks interact directly with the ATM’s computer and force it to dispense money.

“Often the malware requires entering of codes to dispense cash,” reads an FBI affidavit (PDF). “These codes can be obtained by a third party, not at the location, who then provides the codes to the subjects at the ATM. This allows the third party to know how much cash is dispensed from the ATM, preventing those who are physically at the ATM from keeping cash for themselves instead of providing it to the criminal organization. The use of mobile phones is often used to obtain these dispensing codes.” Continue reading →


27
Jan 18

First ‘Jackpotting’ Attacks Hit U.S. ATMs

ATM “jackpotting” — a sophisticated crime in which thieves install malicious software and/or hardware at ATMs that forces the machines to spit out huge volumes of cash on demand — has long been a threat for banks in Europe and Asia, yet these attacks somehow have eluded U.S. ATM operators. But all that changed this week after the U.S. Secret Service quietly began warning financial institutions that jackpotting attacks have now been spotted targeting cash machines here in the United States.

To carry out a jackpotting attack, thieves first must gain physical access to the cash machine. From there they can use malware or specialized electronics — often a combination of both — to control the operations of the ATM.

A keyboard attached to the ATM port. Image: FireEye

On Jan. 21, 2018, KrebsOnSecurity began hearing rumblings about jackpotting attacks, also known as “logical attacks,” hitting U.S. ATM operators. I quickly reached out to ATM giant NCR Corp. to see if they’d heard anything. NCR said at the time it had received unconfirmed reports, but nothing solid yet.

On Jan. 26, NCR sent an advisory to its customers saying it had received reports from the Secret Service and other sources about jackpotting attacks against ATMs in the United States.

“While at present these appear focused on non-NCR ATMs, logical attacks are an industry-wide issue,” the NCR alert reads. “This represents the first confirmed cases of losses due to logical attacks in the US. This should be treated as a call to action to take appropriate steps to protect their ATMs against these forms of attack and mitigate any consequences.”

The NCR memo does not mention the type of jackpotting malware used against U.S. ATMs. But a source close to the matter said the Secret Service is warning that organized criminal gangs have been attacking stand-alone ATMs in the United States using “Ploutus.D,” an advanced strain of jackpotting malware first spotted in 2013.

According to that source — who asked to remain anonymous because he was not authorized to speak on the record — the Secret Service has received credible information that crooks are activating so-called “cash out crews” to attack front-loading ATMs manufactured by ATM vendor Diebold Nixdorf.

The source said the Secret Service is warning that thieves appear to be targeting Opteva 500 and 700 series Dielbold ATMs using the Ploutus.D malware in a series of coordinated attacks over the past 10 days, and that there is evidence that further attacks are being planned across the country.

“The targeted stand-alone ATMs are routinely located in pharmacies, big box retailers, and drive-thru ATMs,” reads a confidential Secret Service alert sent to multiple financial institutions and obtained by KrebsOnSecurity. “During previous attacks, fraudsters dressed as ATM technicians and attached a laptop computer with a mirror image of the ATMs operating system along with a mobile device to the targeted ATM.

Reached for comment, Diebold shared an alert it sent to customers Friday warning of potential jackpotting attacks in the United States. Diebold’s alert confirms the attacks so far appear to be targeting front-loaded Opteva cash machines.

“As in Mexico last year, the attack mode involves a series of different steps to overcome security mechanism and the authorization process for setting the communication with the [cash] dispenser,” the Diebold security alert reads. A copy of the entire Diebold alert, complete with advice on how to mitigate these attacks, is available here (PDF). Continue reading →


5
Dec 17

Anti-Skimmer Detector for Skimmer Scammers

Crooks who make and deploy ATM skimmers are constantly engaged in a cat-and-mouse game with financial institutions, which deploy a variety of technological measures designed to defeat skimming devices. The latest innovation aimed at tipping the scales in favor of skimmer thieves is a small, battery powered device that provides crooks a digital readout indicating whether an ATM likely includes digital anti-skimming technology.

A well-known skimmer thief is marketing a product called “Smart Shield Detector” that claims to be able to detect a variety of electronic methods used by banks to foil ATM skimmers.

The device, which sells for $200, is called a “Smart Shield Detector,” and promises to detect “all kinds of noise shields, hidden shields, delayed shields and others!”

It appears to be a relatively simple machine that gives a digital numeric indicator of whether an ATM uses any of a variety of anti-skimming methods. One of the most common is known as “frequency jamming,” which uses electronic signals to scramble both the clock (timing) and the card data itself in a bid to confuse skimming devices.

“You will see current level within seconds!,” the seller enthuses in an online ad for the product, a snippet of which is shown above. “Available for sale after November 1st, market price 200usd. Preorders available at price 150usd/device. 2+ devices for your team – will give discounts.”

According to the individual selling the Smart Shield Detector, a readout of 15 or higher indicates the presence of some type of electronic shield or jamming technology — warning the skimmer thief to consider leaving that ATM alone and to find a less protected machine. In contrast, a score between 3-5 is meant to indicate “no shield,” i.e., that the ATM is ripe for compromise. Continue reading →


28
Jul 16

Would You Use This ATM?

One basic tenet of computer security is this: If you can’t vouch for a networked thing’s physical security, you cannot also vouch for its cybersecurity. That’s because in most cases, networked things really aren’t designed to foil a skilled and determined attacker who can physically connect his own devices. So you can imagine my shock and horror seeing a Cisco switch and wireless antenna sitting exposed atop of an ATM out in front of a bustling grocery store in my hometown of Northern Virginia.

I’ve long warned readers to avoid stand-alone ATMs in favor of wall-mounted and/or bank-operated ATMs. In many cases, thieves who can access the networking cables of an ATM are hooking up their own sniffing devices to grab cash machine card data flowing across the ATM network in plain text.

But I’ve never before seen a setup quite this braindead. Take a look:

A not-very-secure ATM in front of a grocery store in Northern Virginia.

An ATM in front of a grocery store in Northern Virginia.

Now let’s have a closer look at the back of this machine to see what we’re dealing with:

groceryatmback

Need to get online in a jiffy? No problem, this ATM has plenty of network jacks for you to plug into. What could go wrong?

Daniel Battisto, the longtime KrebsOnSecurity reader who alerted me to this disaster waiting to happen, summed up my thoughts on it pretty well in an email.

“I’d like to assume, for the sake of sanity, that the admin who created this setup knows that Cisco security is broken relatively simple once physical access is gained,” said Battisto, a physical and IT security professional. “I’d also like to assume that all unused interfaces are shutdown, and port-security has been configured on the interfaces in use. I’d also like to assume that the admin established a good console login.” Continue reading →


24
Jun 16

How to Spot Ingenico Self-Checkout Skimmers

A KrebsOnSecurity story last month about credit card skimmers found in self-checkout lanes at some Walmart locations got picked up by quite a few publications. Since then I’ve heard from several readers who work at retailers that use hundreds of thousands of these Ingenico credit card terminals across their stores, and all wanted to know the same thing: How could they tell if their self-checkout lanes were compromised? This post provides a few pointers.

Happily, just days before my story point-of-sale vendor Ingenico produced a tutorial on how to spot a skimmer on self checkout lanes powered by Ingenico iSC250 card terminals. Unfortunately, it doesn’t appear that this report was widely disseminated, because I’m still getting questions from readers at retailers that use these devices.

The red calipers in the image above show the size differences in various noticeable areas of the case overlay on the left compared to the actual ISC250 on the right. Source: Ingenico.

The red calipers in the image above show the size differences in various noticeable areas of the case overlay on the left compared to the actual iSC250 on the right. Source: Ingenico.

“In order for the overlay to fit atop the POS [point-of-sale] terminal, it must be longer and wider than the target device,” reads a May 16, 2016 security bulletin obtained by KrebsOnSecurity. “For this reason, the case overlay will appear noticeably larger than the actual POS terminal. This is the primary identifying characteristic of the skimming device. A skimmer overlay of the iSC250 is over 6 inches wide and 7 inches tall while the iSC250 itself is 5 9/16 inch wide and 6 1⁄2 inches tall.”

In addition, the skimming device that thieves can attach in the blink of an eye on top of the Ingenico self-checkout card reader blocks the backlight from coming through the fake PIN pad overlay.

The backlight can be best seen while shading the keypad from room lights. The image on the left is a powered-on legitimate ISC250 viewed with the keypad shaded. The backlight can be seen in comparison to a powered-off ISC250 in the right image. Source: Ingenico.

The backlight can be best seen while shading the keypad from room lights. The image on the left is a powered-on legitimate iSC250 viewed with the keypad shaded. The backlight can be seen in comparison to a powered-off iSC250 in the right image. Source: Ingenico.

Continue reading →