Cryptocurrency and crime describes notable examples of cybercrime related to theft (or the otherwise illegal acquisition) of cryptocurrencies and some of the methods or security vulnerabilities commonly exploited. Cryptojacking is a form of cybercrime specific to cryptocurrencies that has been used on websites to hijack a victim's resources and use them for hashing and mining cryptocurrencies.
According to blockchain analysis company Chainalysis, cryptocurrency transactions that they were certain involved illicit activities like cybercrime, money laundering and terrorism financing made up 0.15% of transactions conducted in 2021, representing a total of $14 billion.
Background
There are various types of cryptocurrency wallets available, with different layers of security, including devices, software for different operating systems or browsers, and offline wallets.
Novel exploits unique to blockchain transactions exist which aim to create unintended outcomes for those on the other end of a transaction. One of the more well known issues that opens the possibility for exploits on Bitcoin is the transaction malleability problem.
Notable thefts
In 2018, around US$1.7 billion in cryptocurrency was lost to scams, theft and fraud. In the first quarter 2019, the amount of such losses rose to US$1.2 billion.
Exchanges
Notable cryptocurrency exchange compromises resulting in the loss of cryptocurrencies include:
- In 2015, cryptocurrencies worth US$5 million were stolen from Bitstamp.
- Between 2011 and 2014, US$350 million worth of bitcoin were stolen from Mt. Gox.
- In 2016, US$72 million were stolen through exploiting Bitfinex's exchange wallet, users were refunded.
- On December 7, 2017, Slovenian cryptocurrency exchange Nicehash reported that hackers had stolen over $70M using a hijacked company computer.
- On December 19, 2017, Yapian, the owner of South Korean exchange Youbit, filed for bankruptcy after suffering two hacks that year. Customers were still granted access to 75% of their assets.
- In 2018, cryptocurrencies worth US$400 million were stolen from Coincheck.
- In May 2018, Bitcoin Gold had its transactions hijacked and abused by unknown hackers. Exchanges lost an estimated $18m and Bitcoin Gold was delisted from Bittrex after it refused to pay its share of the damages.
- In June 2018, South Korean exchange Coinrail was hacked, losing over $37M worth of cryptos. The hack worsened an already ongoing cryptocurrency selloff by an additional $42 billion.
- On July 9, 2018, the exchange Bancor, whose code and fundraising had been subjects of controversy, had $23.5 million in cryptocurrency stolen.
- Zaif US$60 million in Bitcoin, Bitcoin Cash and Monacoin stolen in September 2018
- Binance In 2019 cryptocurrencies worth US$40 million were stolen.
- Africrypt founders are suspected of absconding in June 2021 with US$3.6 billion worth of Bitcoin
- PolyNetwork (DeFi) suffered the loss of US$611 million in a theft in August 2021.
- Japanese cryptocurrency exchange Liquid was compromised in August 2021 resulting in a loss of US$97 million worth of digital coins
- Cream Finance were subject to a US$29 million theft in August, 2021 and $130 million October 28, 2021.
- On December 2, 2021, users of the BadgerDAO DeFi lost around $118,500,000 worth of bitcoin and $679,000 worth of ethereum tokens in a front-end attack. A compromised API key of the Cloudflare content delivery network account allowed injecting of a malicious script to the web interface. BadgerDAO "paused" all smart contracts due to user complaints.
- On December 6, 2021, the cryptocurrency exchange BitMart lost around $135M worth of Ethereum and an estimate of around $46 million in other cryptocurrencies due to a breach of two of its wallets. Although BitMart stated that it would reimburse its clients, many BitMart clients have not received any money from the exchange as of January 2022.
- On December 12, 2021, users of VulcanForge lost around $135M worth of PYR due to breaches of multiple wallets. Partering centralized exchanges had been notified of the hack and they have pledged to seize any stolen funds upon deposit.
- On January 27, 2022, Qubit Finance (DeFi) lost around $80M worth of Binance Coin due to a flaw in the smart contract that enabled withdrawal of the said amount in exchange for a deposit of 0 ETH.
- On September 20, 2022, Wintermute was hacked $160M due to a technical flaw
Wallets
The Parity Wallet has had two security incidents amounting to 666,773 ETH lost or stolen. In July 2017, due to a bug in the multisignature code, 153,037 ETH (approximately US$32 million at the time) were stolen. In November 2017, a subsequent multisignature flaw in Parity led to a lock-up of 513,774 Ether (about US$150 million at the time) to be unreachable; as of March 2019, the funds were still frozen.
Energy
Notable cases of electricity theft to mine proof-of-work cryptocurrencies include:
- In February 2021 Malaysian police arrested six men involved in a Bitcoin mining operation which had stolen US$2 million in electricity
- Ukraine authorities shutdown an underground gaming and cryptocurrency farm in July, 2021, accused of stealing $259,300 of electricity each month
- In July 2021 Malaysian authorities destroyed 1,069 cryptocurrency mining systems accused of stealing electricity from the grid
- In May, 2021 UK authorities closed a suspected bitcoin mine after Western Power Distribution found an illegal connection to the electricity supply
Blockchains
Bitcoin
There have been many cases of bitcoin theft. As of December 2017, around 980,000 bitcoins—over five percent of all bitcoin in circulation—had been lost on cryptocurrency exchanges.
One type of theft involves a third party accessing the private key to a victim's bitcoin address, or of an online wallet. If the private key is stolen, all the bitcoins from the compromised address can be transferred. In that case, the network does not have any provisions to identify the thief, block further transactions of those stolen bitcoins, or return them to the legitimate owner.
Theft also occurs at sites where bitcoins are used to purchase illicit goods. In late November 2013, an estimated US$100 million in bitcoins were allegedly stolen from the online illicit goods marketplace Sheep Marketplace, which immediately closed. Users tracked the coins as they were processed and converted to cash, but no funds were recovered and no culprits identified. A different black market, Silk Road 2, stated that during a February 2014 hack, bitcoins valued at $2.7 million were taken from escrow accounts.
Sites where users exchange bitcoins for cash or store them in "wallets" are also targets for theft. Inputs.io, an Australian wallet service, was hacked twice in October 2013 and lost more than $1 million in bitcoins. GBL, a Chinese bitcoin trading platform, suddenly shut down on 26 October 2013; subscribers, unable to log in, lost up to $5 million worth of bitcoin. In late February 2014 Mt. Gox, one of the largest virtual currency exchanges, filed for bankruptcy in Tokyo amid reports that bitcoins worth US$350 million had been stolen. Flexcoin, a bitcoin storage specialist based in Alberta, Canada, shut down in March 2014 after saying it discovered a theft of about $650,000 in bitcoins. Poloniex, a digital currency exchange, reported in March 2014 that it lost bitcoins valued at around $50,000. In January 2015 UK-based bitstamp, the third busiest bitcoin exchange globally, was hacked and US$5 million in bitcoins were stolen. February 2015 saw a Chinese exchange named BTER lose bitcoins worth nearly $2 million to hackers.
A major bitcoin exchange, Bitfinex, was hacked and nearly 120,000 bitcoins (around US$60 million) was stolen in 2016. Bitfinex was forced to suspend its trading. The theft was the second largest bitcoin heist ever, dwarfed only by the Mt. Gox theft in 2014. According to Forbes, "All of Bitfinex's customers,... will stand to lose money. The company has announced a cut of 36.067% across the board." Following the hack the company refunded customers. In 2022, the US government recovered 94,636 bitcoin (worth approximately $3.6 billion at time of recovery) from the 2016 thefts of the Bitfinex exchange. By 2022, the amount of bitcoin stolen was worth $4.5 billion. Two people were charged for the thefts.
On May 7, 2019, hackers stole over 7000 Bitcoins from the Binance Cryptocurrency Exchange, at a value of over 40 million US dollars. Binance CEO Zhao Changpeng stated: "The hackers used a variety of techniques, including phishing, viruses and other attacks.... The hackers had the patience to wait, and execute well-orchestrated actions through multiple seemingly independent accounts at the most opportune time."
Thefts have raised safety concerns. Charles Hayter, founder of digital currency comparison website CryptoCompare said, "It's a reminder of the fragility of the infrastructure in such a nascent industry."[54] According to the hearing of U.S. House of Representatives Committee on Small Business on April 2, 2014, "these vendors lack regulatory oversight, minimum capital standards and don't provide consumer protection against loss or theft."
Ethereum
In 2016, known as the DAO event, an exploit in the original Ethereum smart contracts resulted in multiple transactions, creating additional US$50 million. Subsequently, the currency was forked into Ethereum Classic, and Ethereum, with the latter continuing with the new blockchain without the exploited transactions.
On November 21, 2017, Tether announced that it had been hacked, losing $31 million in USDT from its core treasury wallet. The company has 'tagged' the stolen currency, hoping to 'lock' them in the hacker's wallet (making them unspendable).
In 2022, hackers created a signature account on a blockchain bridge called "Wormhole" and stole more than $300M worth of ether.
Fraud
Josh Garza, who founded the cryptocurrency startups GAW Miners and ZenMiner in 2014, acknowledged in a plea agreement that the companies were part of a pyramid scheme, and pleaded guilty to wire fraud in 2015. The U.S. Securities and Exchange Commission separately brought a civil enforcement action against Garza, who was eventually ordered to pay a judgment of US$9.1 million plus $700,000 in interest. The SEC's complaint stated that Garza, through his companies, had fraudulently sold "investment contracts representing shares in the profits they claimed would be generated" from mining.
Following its shut-down, in 2018 a class action lawsuit for $771,000 was filed against the cryptocurrency platform known as BitConnect, including the platform promoting YouTube channels. Prior fraud warnings in regards to BitConnect, and cease-and-desist orders by the Texas State Securities Board cited the promise of massive monthly returns.
BitConnect founder and promoters diverted $2 billion in investor funds into personally controlled digital wallets between 2017 and 2018, according to the US Securities and Exchange Commission. The scam purported to use a "crypto trading bot" for a guaranteed return on investment. In reality no such mechanism was implemented and a network of promoters were paid a commission to attract new investors. Lead promotor, Glenn Arcaro, pled guilty to criminal charges.
OneCoin was a massive world-wide multi-level marketing Ponzi scheme promoted as (but not involving) a cryptocurrency, causing losses of US$4 billion worldwide. Several people behind the scheme were arrested in 2018 and 2019.
The cryptocurrency community refers to pre-mining, hidden launches, ICO or extreme rewards for the altcoin founders as deceptive practices. This is at times an inherent part of the cryptocurrency's design. Pre-mining refers to the practice of generating the currency before its released to the public.
Malware
Malware attacks
Some malware can steal private keys for bitcoin wallets allowing the bitcoins themselves to be stolen. The most common type searches computers for cryptocurrency wallets to upload to a remote server where they can be cracked and their coins stolen. Many of these also log keystrokes to record passwords, often avoiding the need to crack the keys. A different approach detects when a bitcoin address is copied to a clipboard and quickly replaces it with a different address, tricking people into sending bitcoins to the wrong address. This method is effective because bitcoin transactions are irreversible.
One virus, spread through the Pony botnet, was reported in February 2014 to have stolen up to $220,000 in cryptocurrencies including bitcoins from 85 wallets. Security company Trustwave, which tracked the malware, reports that its latest version was able to steal 30 types of digital currency.
A type of Mac malware active in August 2013, Bitvanity posed as a vanity wallet address generator and stole addresses and private keys from other bitcoin client software. A different trojan for macOS, called CoinThief was reported in February 2014 to be responsible for multiple bitcoin thefts. The software was hidden in versions of some cryptocurrency apps on Download.com and MacUpdate.
Ransomware
Many types of ransomware demand payment in bitcoin. One program called CryptoLocker, typically spread through legitimate-looking email attachments, encrypts the hard drive of an infected computer, then displays a countdown timer and demands a ransom in bitcoin, to decrypt it. Massachusetts police said they paid a 2 bitcoin ransom in November 2013, worth more than $1,300 at the time, to decrypt one of their hard drives. Bitcoin was used as the ransom medium in the WannaCry ransomware. One ransomware variant disables internet access and demands credit card information to restore it, while secretly mining bitcoins.
As of June 2018, most ransomware attackers preferred to use currencies other than bitcoin, with 44% of attacks in the first half of 2018 demanding Monero, which is highly private and difficult to trace, compared to 10% for bitcoin and 11% for Ether.
Unauthorized mining
In June 2011, Symantec warned about the possibility that botnets could mine covertly for bitcoins. Malware used the parallel processing capabilities of GPUs built into many modern video cards. Although the average PC with an integrated graphics processor is virtually useless for bitcoin mining, tens of thousands of PCs laden with mining malware could produce some results.
In mid-August 2011, bitcoin mining botnets were detected, and less than three months later, bitcoin mining trojans had infected Mac OS X.
In April 2013, electronic sports organization E-Sports Entertainment was accused of hijacking 14,000 computers to mine bitcoins; the company later settled the case with the State of New Jersey.
German police arrested two people in December 2013 who customized existing botnet software to perform bitcoin mining, which police said had been used to mine at least $950,000 worth of bitcoins.
For four days in December 2013 and January 2014, Yahoo! Europe hosted an ad containing bitcoin mining malware that infected an estimated two million computers. The software, called Sefnit, was first detected in mid-2013 and has been bundled with many software packages. Microsoft has been removing the malware through its Microsoft Security Essentials and other security software.
Several reports of employees or students using university or research computers to mine bitcoins have been published.
On February 20, 2014, a member of the Harvard community was stripped of his or her access to the University's research computing facilities after setting up a Dogecoin mining operation using a Harvard research network, according to an internal email circulated by Faculty of Arts and Sciences Research Computing officials.
Ars Technica reported in January 2018 that YouTube advertisements contained JavaScript code that mined the cryptocurrency Monero.
Phishing
A phishing website to generate private IOTA wallet seed passphrases, collected wallet keys, with estimates of up to US$4 million worth of MIOTA tokens stolen. The malicious website operated for an unknown amount of time, and was discovered in January 2018.
Other incidents
In 2015, two members of the Silk Road Task Force—a multi-agency federal task force that carried out the U.S. investigation of Silk Road—were convicted over charges pertaining to corruption. Former DEA agent, Carl Mark Force, had attempted to extort Silk Road founder Ross Ulbricht ("Dread Pirate Roberts") by faking the murder of an informant. He pleaded guilty to money laundering, obstruction of justice, and extortion under color of official right, and was sentenced to 6.5 years in a federal prison. Former U.S. Secret Service agent, Shaun Bridges, pleaded guilty to crimes relating to his diversion of $800,000 worth of bitcoins to his personal account during the investigation, and also separately pleaded guilty to money laundering in connection to another cryptocurrency theft. Bridges was sentenced to almost eight years in federal prison.
Gerald Cotten founded QuadrigaCX in 2013, after graduating from the Schulich school of Business in Toronto. Cotten was acting as the sole curator of the exchange. Quadriga had no official bank accounts, since banks at the time had no method of managing cryptocurrency. In late 2018, Canada's largest crypto exchange QuadrigaCX lost US$190 million in cryptocurrency when the owner died; he was the only one with knowledge of the password to a storage wallet. The exchange filed for bankruptcy in 2019.
Michael Terpin, the founder and chief executive officer of Transform Group, a San Juan, Puerto Rico-based company that advises blockchain businesses on public relations and communications, sued Ellis Pinsky in New York on May 7, 2020, for leading a "sophisticated cybercrime spree" that stole US$24 million in cryptocurrency by hacking into Terpin's phone in 2018. Terpin also sued Nicholas Truglia and won a $75.8 million judgment against Truglia in 2019 in California state court.
On July 15, 2020, Twitter accounts of prominent personalities and firms, including Joe Biden, Barack Obama, Bill Gates, Elon Musk, Jeff Bezos, Apple, Kanye West, Michael Bloomberg and Uber were hacked. Twitter confirmed that it was a coordinated social engineering attack on their own employees. Twitter released its statement six hours after the attack took place. Hackers posted the message to transfer the Bitcoin in a Bitcoin wallet, which would double the amount. The wallet's balance was expected to increase to more than $100,000 as the message spread among the Twitter followers.
In 2022, the Federal Trade Commission reported that $139 million in cryptocurrency was stolen by romance scammers in 2020. Some scammers targeted dating apps with fake profiles.
In early 2022, the Beanstalk cryptocurrency was stripped of its reserves, which were valued at more than US$180 million, after attackers had managed to use borrowed US$80 million in cryptocurrency to buy enough voting rights to transfer the reserves to their own accounts outside the system. It was initially unclear, if such an exploit of governance procedures was illegal.
