First ‘Jackpotting’ Attacks Hit U.S. ATMs

January 27, 2018
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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 →

Registered at SSA.GOV? Good for You, But Keep Your Guard Up

January 26, 2018
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KrebsOnSecurity has long warned readers to plant your own flag at the my Social Security online portal of the U.S. Social Security Administration (SSA) — even if you are not yet drawing benefits from the agency — because identity thieves have been registering accounts in peoples’ names and siphoning retirement and/or disability funds. This is the story of a Midwest couple that took all the right precautions and still got hit by ID thieves who impersonated them to the SSA directly over the phone.

In mid-December 2017 this author heard from Ed Eckenstein, a longtime reader in Oklahoma whose wife Ruth had just received a snail mail letter from the SSA about successfully applying to withdraw benefits. The letter confirmed she’d requested a one-time transfer of more than $11,000 from her SSA account. The couple said they were perplexed because both previously had taken my advice and registered accounts with MySocialSecurity, even though Ruth had not yet chosen to start receiving SSA benefits.

The fraudulent one-time payment that scammers tried to siphon from Ruth Eckenstein’s Social Security account.

Sure enough, when Ruth logged into her MySocialSecurity account online, there was a pending $11,665 withdrawal destined to be deposited into a Green Dot prepaid debit card account (funds deposited onto a Green Dot card can be spent like cash at any store that accepts credit or debit cards). The $11,655 amount was available for a one-time transfer because it was intended to retroactively cover monthly retirement payments back to her 65th birthday.

The letter the Eckensteins received from the SSA indicated that the benefits had been requested over the phone, meaning the crook(s) had called the SSA pretending to be Ruth and supplied them with enough information about her to enroll her to begin receiving benefits. Ed said he and his wife immediately called the SSA to notify them of fraudulent enrollment and pending withdrawal, and they were instructed to appear in person at an SSA office in Oklahoma City.

The SSA ultimately put a hold on the fraudulent $11,665 transfer, but Ed said it took more than four hours at the SSA office to sort it all out. Mr. Eckenstein said the agency also informed them that the thieves had signed his wife up for disability payments. In addition, her profile at the SSA had been changed to include a phone number in the 786 area code (Miami, Fla.).

“They didn’t change the physical address perhaps thinking that would trigger a letter to be sent to us,” Ed explained.

Thankfully, the SSA sent a letter anyway. Ed said many additional hours spent researching the matter with SSA personnel revealed that in order to open the claim on Ruth’s retirement benefits, the thieves had to supply the SSA with a short list of static identifiers about her, including her birthday, place of birth, mother’s maiden name, current address and phone number.

Unfortunately, most (if not all) of this data is available on a broad swath of the American populace for free online (think Zillow, Ancestry.com, Facebook, etc.) or else for sale in the cybercrime underground for about the cost of a latte at Starbucks.

The Eckensteins thought the matter had been resolved until Jan. 14, when Ruth received a 1099 form from the SSA indicating they’d reported to the IRS that she had in fact received an $11,665 payment.

“We’ve emailed our tax guy for guidance on how to deal with this on our taxes,” Mr. Eckenstein wrote in an email to KrebsOnSecurity. “My wife logged into SSA portal and there was a note indicating that corrected/updated 1099s would be available at the end of the month. She’s not sure whether that message was specific to her or whether everyone’s seeing that.” Continue reading →

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Chronicle: A Meteor Aimed At Planet Threat Intel?

January 24, 2018
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Alphabet Inc., the parent company of Google, said today it is in the process of rolling out a new service designed to help companies more quickly make sense of and act on the mountains of threat data produced each day by cybersecurity tools.

Countless organizations rely on a hodgepodge of security software, hardware and services to find and detect cybersecurity intrusions before an incursion by malicious software or hackers has the chance to metastasize into a full-blown data breach.

The problem is that the sheer volume of data produced by these tools is staggering and increasing each day, meaning already-stretched IT staff often miss key signs of an intrusion until it’s too late.

Enter “Chronicle,” a nascent platform that graduated from the tech giant’s “X” division, which is a separate entity tasked with tackling hard-to-solve problems with an eye toward leveraging the company’s core strengths: Massive data analytics and storage capabilities, machine learning and custom search capabilities.

“We want to 10x the speed and impact of security teams’ work by making it much easier, faster and more cost-effective for them to capture and analyze security signals that have previously been too difficult and expensive to find,” wrote Stephen Gillett, CEO of the new venture.

Few details have been released yet about how exactly Chronicle will work, although the company did say it would draw in part on data from VirusTotal, a free service acquired by Google in 2012 that allows users to scan suspicious files against dozens of commercial antivirus tools simultaneously.

Gillett said his division is already trialing the service with several Fortune 500 firms to test the preview release of Chronicle, but the company declined to name any of those participating.

ANALYSIS

It’s not terribly clear from Gillett’s post or another blog post from Alphabet’s X division by Astro Teller how exactly Chronicle will differentiate itself in such a crowded market for cybersecurity offerings. But it’s worth considering the impact that VirusTotal has had over the years.

Currently, VirusTotal handles approximately one million submissions each day. The results of each submission get shared back with the entire community of antivirus vendors who lend their tools to the service — which allows each vendor to benefit by adding malware signatures for new variants that their tools missed but that a preponderance of other tools flagged as malicious.

Naturally, cybercriminals have responded by creating their own criminal versions of VirusTotal: So-called “no distribute” scanners. These services cater to malware authors, and use the same stable of antivirus tools, except they prevent these tools from phoning home to the antivirus companies about new, unknown variants. Continue reading →

Expert: IoT Botnets the Work of a ‘Vast Minority’

January 24, 2018
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In December 2017, the U.S. Department of Justice announced indictments and guilty pleas by three men in the United States responsible for creating and using Mirai, a malware strain that enslaves poorly-secured “Internet of Things” or IoT devices like security cameras and digital video recorders for use in large-scale cyberattacks.

The FBI and the DOJ had help in their investigation from many security experts, but this post focuses on one expert whose research into the Dark Web and its various malefactors was especially useful in that case. Allison Nixon is director of security research at Flashpoint, a cyber intelligence firm based in New York City. Nixon spoke with KrebsOnSecurity at length about her perspectives on IoT security and the vital role of law enforcement in this fight.

Brian Krebs (BK): Where are we today with respect to IoT security? Are we better off than were a year ago, or is the problem only worse?

Allison Nixon (AN): In some aspects we’re better off. The arrests that happened over the last year in the DDoS space, I would call that a good start, but we’re not out of the woods yet and we’re nowhere near the end of anything.

BK: Why not?

AN: Ultimately, what’s going with these IoT botnets is crime. People are talking about these cybersecurity problems — problems with the devices, etc. — but at the end of the day it’s crime and private citizens don’t have the power to make these bad actors stop.

BK: Certainly security professionals like yourself and others can be diligent about tracking the worst actors and the crime machines they’re using, and in reporting those systems when it’s advantageous to do so?

AN: That’s a fair argument. I can send abuse complaints to servers being used maliciously. And people can write articles that name individuals. However, it’s still a limited kind of impact. I’ve seen people get named in public and instead of stopping, what they do is improve their opsec [operational security measures] and keep doing the same thing but just sneakier. In the private sector, we can frustrate things, but we can’t actually stop them in the permanent, sanctioned way that law enforcement can. We don’t really have that kind of control.

BK: How are we not better off?

AN: I would say that as time progresses, the community that practices DDoS and malicious hacking and these pointless destructive attacks get more technically proficient when they’re executing attacks, and they just become a more difficult adversary.

BK: A more difficult adversary?

AN: Well, if you look at the individuals that were the subject of the announcement this month, and you look in their past, you can see they’ve been active in the hacking community a long time. Litespeed [the nickname used by Josiah White, one of the men who pleaded guilty to authoring Mirai] has been credited with lots of code.  He’s had years to develop and as far as I could tell he didn’t stop doing criminal activity until he got picked up by law enforcement.

BK: It seems to me that the Mirai authors probably would not have been caught had they never released the source code for their malware. They said they were doing so because multiple law enforcement agencies and security researchers were hot on their trail and they didn’t want to be the only ones holding the source code when the cops showed up at their door. But if that was really their goal in releasing it, doing so seems to have had the exact opposite effect. What’s your take on that?

AN: You are absolutely, 100 million percent correct. If they just shut everything down and left, they’d be fine now. The fact that they dumped the source was a tipping point of sorts. The damages they caused at that time were massive, but when they dumped the source code the amount of damage their actions contributed to ballooned [due to the proliferation of copycat Mirai botnets]. The charges against them specified their actions in infecting the machines they controlled, but when it comes to what interested researchers in the private sector, the moment they dumped the source code — that’s the most harmful act they did out of the entire thing.

BK: Do you believe their claimed reason for releasing the code?

AN: I believe it. They claimed they released it because they wanted to hamper investigative efforts to find them. The problem is that not only is it incorrect, it also doesn’t take into account the researchers on the other end of the spectrum who have to pick from many targets to spend their time looking at. Releasing the source code changed that dramatically. It was like catnip to researchers, and was just a new thing for researchers to look at and play with and wonder who wrote it.

If they really wanted to stay off law enforcement’s radar, they would be as low profile as they could and not be interesting. But they did everything wrong: They dumped the source code and attacked a security researcher using tools that are interesting to security researchers. That’s like attacking a dog with a steak. I’m going to wave this big juicy steak at a dog and that will teach him. They made every single mistake in the book.

BK: What do you think it is about these guys that leads them to this kind of behavior? Is it just a kind of inertia that inexorably leads them down a slippery slope if they don’t have some kind of intervention?

AN: These people go down a life path that does not lead them to a legitimate livelihood. They keep doing this and get better at it and they start to do these things that really can threaten the Internet as a whole. In the case of these DDoS botnets, it’s worrying that these individuals are allowed to go this deep before law enforcement catches them. Continue reading →

Some Basic Rules for Securing Your IoT Stuff

January 17, 2018
60 Comments

Most readers here have likely heard or read various prognostications about the impending doom from the proliferation of poorly-secured “Internet of Things” or IoT devices. Loosely defined as any gadget or gizmo that connects to the Internet but which most consumers probably wouldn’t begin to know how to secure, IoT encompasses everything from security cameras, routers and digital video recorders to printers, wearable devices and “smart” lightbulbs.

Throughout 2016 and 2017, attacks from massive botnets made up entirely of hacked IoT devices had many experts warning of a dire outlook for Internet security. But the future of IoT doesn’t have to be so bleak. Here’s a primer on minimizing the chances that your IoT things become a security liability for you or for the Internet at large.

-Rule #1: Avoid connecting your devices directly to the Internet — either without a firewall or in front it, by poking holes in your firewall so you can access them remotely. Putting your devices in front of your firewall is generally a bad idea because many IoT products were simply not designed with security in mind and making these things accessible over the public Internet could invite attackers into your network. If you have a router, chances are it also comes with a built-in firewall. Keep your IoT devices behind the firewall as best you can.

-Rule #2: If you can, change the thing’s default credentials to a complex password that only you will know and can remember. And if you do happen to forget the password, it’s not the end of the world: Most devices have a recessed reset switch that can be used to restore to the thing to its factory-default settings (and credentials). Here’s some advice on picking better ones.

I say “if you can,” at the beginning of Rule #2 because very often IoT devices — particularly security cameras and DVRs — are so poorly designed from a security perspective that even changing the default password to the thing’s built-in Web interface does nothing to prevent the things from being reachable and vulnerable once connected to the Internet.

Also, many of these devices are found to have hidden, undocumented “backdoor” accounts that attackers can use to remotely control the devices. That’s why Rule #1 is so important. Continue reading →

Serial SWATter Tyler “SWAuTistic” Barriss Charged with Involuntary Manslaughter

January 15, 2018
83 Comments

Tyler Raj Barriss, a 25-year-old serial “swatter” whose phony emergency call to Kansas police last month triggered a fatal shooting, has been charged with involuntary manslaughter and faces up to eleven years in prison.

Tyler Raj Barriss, in an undated selfie.

Barriss’s online alias — “SWAuTistic” — is a nod to a dangerous hoax known as “swatting,” in which the perpetrator spoofs a call about a hostage situation or other violent crime in progress in the hopes of tricking police into responding at a particular address with potentially deadly force.

Barriss was arrested in Los Angeles this month for alerting authorities in Kansas to a fake hostage situation at an address in Wichita, Kansas on Dec. 28, 2017.

Police responding to the alert surrounded the home at the address Barriss provided and shot 28-year old Andrew Finch as he emerged from the doorway of his mother’s home. Finch, a father of two, was unarmed, and died shortly after being shot by police.

The officer who fired the shot that killed Finch has been identified as a seven-year veteran with the Wichita department. He has been placed on administrative leave pending an internal investigation.

Following his arrest, Barriss was extradited to a Wichita jail, where he had his first court appearance via video on Friday. The Los Angeles Times reports that Barriss was charged with involuntary manslaughter and could face up to 11 years and three months in prison if convicted.

The moment that police in Kansas fired a single shot that killed Andrew Finch (in doorway of his mother’s home).

Barriss also was charged with making a false alarm — a felony offense in Kansas. His bond was set at $500,000.

Sedgwick County District Attorney Marc Bennett told the The LA Times Barriss made the fake emergency call at the urging of several other individuals, and that authorities have identified other “potential suspects” that may also face criminal charges. Continue reading →

Canadian Police Charge Operator of Hacked Password Service Leakedsource.com

January 15, 2018
31 Comments

Canadian authorities have arrested and charged a 27-year-old Ontario man for allegedly selling billions of stolen passwords online through the now-defunct service Leakedsource.com.

The now-defunct Leakedsource service.

On Dec. 22, 2017, the Royal Canadian Mounted Police (RCMP) charged Jordan Evan Bloom of Thornhill, Ontario for trafficking in identity information, unauthorized use of a computer, mischief to data, and possession of property obtained by crime. Bloom is expected to make his first court appearance today.

According to a statement from the RCMP, “Project Adoration” began in 2016 when the RCMP learned that LeakedSource.com was being hosted by servers located in Quebec.

“This investigation is related to claims about a website operator alleged to have made hundreds of thousands of dollars selling personal information,” said Rafael Alvarado, the officer in charge of the RCMP Cybercrime Investigative Team. “The RCMP will continue to work diligently with our domestic and international law enforcement partners to prosecute online criminality.”

In January 2017, multiple news outlets reported that unspecified law enforcement officials had seized the servers for Leakedsource.com, perhaps the largest online collection of usernames and passwords leaked or stolen in some of the worst data breaches — including three billion credentials for accounts at top sites like LinkedIn and Myspace.

Jordan Evan Bloom. Photo: RCMP.

LeakedSource in October 2015 began selling access to passwords stolen in high-profile breaches. Enter any email address on the site’s search page and it would tell you if it had a password corresponding to that address. However, users had to select a payment plan before viewing any passwords.

The RCMP alleges that Jordan Evan Bloom was responsible for administering the LeakedSource.com website, and earned approximately $247,000 from trafficking identity information.

A February 2017 story here at KrebsOnSecurity examined clues that LeakedSource was administered by an individual in the United States.  Multiple sources suggested that one of the administrators of LeakedSource also was the admin of abusewith[dot]us, a site unabashedly dedicated to helping people hack email and online gaming accounts. Continue reading →

Bitcoin Blackmail by Snail Mail Preys on Those with Guilty Conscience

January 11, 2018
98 Comments

KrebsOnSecurity heard from a reader whose friend recently received a remarkably customized extortion letter via snail mail that threatened to tell the recipient’s wife about his supposed extramarital affairs unless he paid $3,600 in bitcoin. The friend said he had nothing to hide and suspects this is part of a random but well-crafted campaign to prey on men who may have a guilty conscience.

The letter addressed the recipient by his first name and hometown throughout, and claimed to have evidence of the supposed dalliances.

“You don’t know me personally and nobody hired me to look into you,” the letter begins. “Nor did I go out looking to burn you. It is just your bad luck that I stumbled across your misadventures while working on a job around Bellevue.”

The missive continues:

“I then put in more time than I probably should have looking into your life. Frankly, I am ready to forget all about you and let you get on with your life. And I am going to give you two options that will accomplish that very thing. These two options are to either ignore this letter, or simply pay me $3,600. Let’s examine those two options in more detail.”

The letter goes on to say that option 1 (ignoring the threat) means the author will send copies of his alleged evidence to the man’s wife and to her friends and family if he does not receive payment within 12 days of the letter’s post marked date.

“So [name omitted], even if you decide to come clean with your wife, it won’t protect her from the humiliation she will feel when her friends and family find out your sordid details from me,” the extortionist wrote. Continue reading →

Microsoft’s Jan. 2018 Patch Tuesday Lowdown

January 10, 2018
81 Comments

Microsoft on Tuesday released 14 security updates, including fixes for the Spectre and Meltdown flaws detailed last week, as well as a zero-day vulnerability in Microsoft Office that is being exploited in the wild. Separately, Adobe pushed a security update to its Flash Player software.

Last week’s story, Scary Chip Flaws Raise Spectre of Meltdown, sought to explain the gravity of these two security flaws present in most modern computers, smartphones, tablets and mobile devices. The bugs are thought to be mainly exploitable in chips made by Intel and ARM, but researchers said it was possible they also could be leveraged to steal data from computers with chips made by AMD.

By the time that story had published, Microsoft had already begun shipping an emergency update to address the flaws, but many readers complained that their PCs experienced the dreaded “blue screen of death” (BSOD) after applying the update. Microsoft warned that the BSOD problems were attributable to many antivirus programs not yet updating their software to play nice with the security updates.

On Tuesday, Microsoft said it was suspending the patches for computers running AMD chipsets.

“After investigating, Microsoft determined that some AMD chipsets do not conform to the documentation previously provided to Microsoft to develop the Windows operating system mitigations to protect against the chipset vulnerabilities known as Spectre and Meltdown,” the company said in a notice posted to its support site.

“To prevent AMD customers from getting into an unbootable state, Microsoft has temporarily paused sending the following Windows operating system updates to devices that have impacted AMD processors,” the company continued. “Microsoft is working with AMD to resolve this issue and resume Windows OS security updates to the affected AMD devices via Windows Update and WSUS as soon as possible.”

In short, if you’re running Windows on a computer powered by an AMD, you’re not going to be offered the Spectre/Meltdown fixes for now. Not sure whether your computer has an Intel or AMD chip? Most modern computers display this information (albeit very briefly) when the computer first starts up, before the Windows logo appears on the screen.

Here’s another way. From within Windows, users can find this information by pressing the Windows key on the keyboard and the “Pause” key at the same time, which should open the System Properties feature. The chip maker will be displayed next to the “Processor:” listing on that page.

Microsoft also on Tuesday provided more information about the potential performance impact on Windows computers after installing the Spectre/Meltdown updates. To summarize, Microsoft said Windows 7, 8.1 and 10 users on older chips (circa 2015 or older), as well as Windows server users on any silicon, are likely to notice a slowdown of their computer after applying this update.

Any readers who experience a BSOD after applying January’s batch of updates may be able to get help from Microsoft’s site: Here are the corresponding help pages for Windows 7, Windows 8.1 and Windows 10 users.

As evidenced by this debacle, it’s a good idea to get in the habit of backing up your system on a regular basis. I typically do this at least once a month — but especially right before installing any updates from Microsoft.  Continue reading →

Website Glitch Let Me Overstock My Coinbase

January 9, 2018
56 Comments

Coinbase and Overstock.com just fixed a serious glitch that allowed Overstock customers to buy any item at a tiny fraction of the listed price. Potentially more punishing, the flaw let anyone paying with bitcoin reap many times the authorized bitcoin refund amount on any canceled Overstock orders.

In January 2014, Overstock.com partnered with Coinbase to let customers pay for merchandise using bitcoin, making it among the first of the largest e-commerce vendors to accept the virtual currency.

On December 19, 2017, as the price of bitcoin soared to more than $17,000 per coin, Coinbase added support for Bitcoin Cash — an offshoot (or “fork”) from bitcoin designed to address the cryptocurrency’s scalability challenges.

As a result of the change, Coinbase customers with balances of bitcoin at the time of the fork were given an equal amount of bitcoin cash stored by Coinbase. However, there is a significant price difference between the two currencies: A single bitcoin is worth almost $15,000 right now, whereas a unit of bitcoin cash is valued at around $2,400.

On Friday, Jan. 5, KrebsOnSecurity was contacted by JB Snyder, owner of North Carolina-based Bancsec, a company that gets paid to break into banks and test their security. An early adopter of bitcoin, Snyder said he was using some of his virtual currency to purchase an item at Overstock when he noticed something alarming.

During the checkout process for those paying by bitcoin, Overstock.com provides the customer a bitcoin wallet address that can be used to pay the invoice and complete the transaction. But Snyder discovered that Overstock’s site just as happily accepted bitcoin cash as payment, even though bitcoin cash is currently worth only about 15 percent of the value of bitcoin.

To confirm and replicate Snyder’s experience firsthand, KrebsOnSecurity purchased a set of three outdoor solar lamps from Overstock for a grand total of $78.27.

The solar lights I purchased from Overstock.com to test Snyder’s finding. They cost $78.27 in bitcoin, but because I was able to pay for them in bitcoin cash I only paid $12.02.

After indicating I wished to pay for the lamps in bitcoin, the site produced a payment invoice instructing me to send exactly 0.00475574 bitcoins to a specific address.

The payment invoice I received from Overstock.com.

Logging into Coinbase, I took the bitcoin address and pasted that into the “pay to:” field, and then told Coinbase to send 0.00475574 in bitcoin cash instead of bitcoin. The site responded that the payment was complete. Within a few seconds I received an email from Overstock congratulating me on my purchase and stating that the items would be shipped shortly.

I had just made a $78 purchase by sending approximately USD $12 worth of bitcoin cash. Crypto-currency alchemy at last!

But that wasn’t the worst part. I didn’t really want the solar lights, but also I had no interest in ripping off Overstock. So I cancelled the order. To my surprise, the system refunded my purchase in bitcoin, not bitcoin cash!

Consider the implications here: A dishonest customer could have used this bug to make ridiculous sums of bitcoin in a very short period of time. Let’s say I purchased one of the more expensive items for sale on Overstock, such as this $100,000, 3-carat platinum diamond ring. I then pay for it in Bitcoin cash, using an amount equivalent to approximately 1 bitcoin ($~15,000).

Then I simply cancel my order, and Overstock/Coinbase sends me almost $100,000 in bitcoin, netting me a tidy $85,000 profit. Rinse, wash, repeat. Continue reading →