Phishers are Angling for Your Cloud Providers

August 30, 2019

Many companies are now outsourcing their marketing efforts to cloud-based Customer Relationship Management (CRM) providers. But when accounts at those CRM providers get hacked or phished, the results can be damaging for both the client’s brand and their customers. Here’s a look at a recent CRM-based phishing campaign that targeted customers of Fortune 500 construction equipment vendor United Rentals.

Stamford, Ct.-based United Rentals [NYSE:URI] is the world’s largest equipment rental company, with some 18,000 employees and earnings of approximately $4 billion in 2018. On August 21, multiple United Rental customers reported receiving invoice emails with booby-trapped links that led to a malware download for anyone who clicked.

While phony invoices are a common malware lure, this particular campaign sent users to a page on United Rentals’ own Web site (unitedrentals.com).

A screen shot of the malicious email that spoofed United Rentals.

In a notice to customers, the company said the unauthorized messages were not sent by United Rentals. One source who had at least two employees fall for the scheme forwarded KrebsOnSecurity a response from UR’s privacy division, which blamed the incident on a third-party advertising partner.

“Based on current knowledge, we believe that an unauthorized party gained access to a vendor platform United Rentals uses in connection with designing and executing email campaigns,” the response read.

“The unauthorized party was able to send a phishing email that appears to be from United Rentals through this platform,” the reply continued. “The phishing email contained links to a purported invoice that, if clicked on, could deliver malware to the recipient’s system. While our investigation is continuing, we currently have no reason to believe that there was unauthorized access to the United Rentals systems used by customers, or to any internal United Rentals systems.”

United Rentals told KrebsOnSecurity that its investigation so far reveals no compromise of its internal systems.

“At this point, we believe this to be an email phishing incident in which an unauthorized third party used a third-party system to generate an email campaign to deliver what we believe to be a banking trojan,” said Dan Higgins, UR’s chief information officer.

United Rentals would not name the third party marketing firm thought to be involved, but passive DNS lookups on the UR subdomain referenced in the phishing email (used by UL for marketing since 2014 and visible in the screenshot above as “wVw.unitedrentals.com”) points to Pardot, an email marketing division of cloud CRM giant Salesforce. Continue reading

Ransomware Bites Dental Data Backup Firm

August 29, 2019

PerCSoft, a Wisconsin-based company that manages a remote data backup service relied upon by hundreds of dental offices across the country, is struggling to restore access to client systems after falling victim to a ransomware attack.

West Allis, Wis.-based PerCSoft is a cloud management provider for Digital Dental Record (DDR), which operates an online data backup service called DDS Safe that archives medical records, charts, insurance documents and other personal information for various dental offices across the United States.

The ransomware attack hit PerCSoft on the morning of Monday, Aug. 26, and encrypted dental records for some — but not all — of the practices that rely on DDS Safe.

PercSoft did not respond to requests for comment. But Brenna Sadler, director of  communications for the Wisconsin Dental Association, said the ransomware encrypted files for approximate 400 dental practices, and that somewhere between 80-100 of those clients have now had their files restored.

Sadler said she did not know whether PerCSoft and/or DDR had paid the ransom demand, what ransomware strain was involved, or how much the attackers had demanded.

But updates to PerCSoft’s Facebook page and statements published by both PerCSoft and DDR suggest someone may have paid up: The statements note that both companies worked with a third party software company and were able to obtain a decryptor to help clients regain access to files that were locked by the ransomware.

Update: Several sources are now reporting that PerCSoft did pay the ransom, although it is not clear how much was paid. One member of a private Facebook group dedicated to IT professionals serving the dental industry shared the following screenshot, which is purportedly from a conversation between PerCSoft and an affected dental office, indicating the cloud provider was planning to pay the ransom:

Another image shared by members of that Facebook group indicates the ransomware that attacked PerCSoft is an extremely advanced and fairly recent strain known variously as REvil and Sodinokibi.

Original story:

However, some affected dental offices have reported that the decryptor did not work to unlock at least some of the files encrypted by the ransomware. Meanwhile, several affected dentistry practices said they feared they might be unable to process payroll payments this week as a result of the attack. Continue reading

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Cybersecurity Firm Imperva Discloses Breach

August 27, 2019

Imperva, a leading provider of Internet firewall services that help Web sites block malicious cyberattacks, alerted customers on Tuesday that a recent data breach exposed email addresses, scrambled passwords, API keys and SSL certificates for a subset of its firewall users.

Redwood Shores, Calif.-based Imperva sells technology and services designed to detect and block various types of malicious Web traffic, from denial-of-service attacks to digital probes aimed at undermining the security of Web-based software applications.

Image: Imperva

Earlier today, Imperva told customers that it learned on Aug. 20 about a security incident that exposed sensitive information for some users of Incapsula, the company’s cloud-based Web Application Firewall (WAF) product.

“On August 20, 2019, we learned from a third party of a data exposure that impacts a subset of customers of our Cloud WAF product who had accounts through September 15, 2017,” wrote Heli Erickson, director of analyst relations at Imperva.

“We want to be very clear that this data exposure is limited to our Cloud WAF product,” Erickson’s message continued. “While the situation remains under investigation, what we know today is that elements of our Incapsula customer database from 2017, including email addresses and hashed and salted passwords, and, for a subset of the Incapsula customers from 2017, API keys and customer-provided SSL certificates, were exposed.”

Companies that use the Incapsula WAF route all of their Web site traffic through the service, which scrubs the communications for any suspicious activity or attacks and then forwards the benign traffic on to its intended destination.

Rich Mogull, founder and vice president of product at Kansas City-based cloud security firm DisruptOps, said Imperva is among the top three Web-based firewall providers in business today.

According to Mogull, an attacker in possession of a customer’s API keys and SSL certificates could use that access to significantly undermine the security of traffic flowing to and from a customer’s various Web sites.

At a minimum, he said, an attacker in possession of these key assets could reduce the security of the WAF settings and exempt or “whitelist” from the WAF’s scrubbing technology any traffic coming from the attacker. A worst-case scenario could allow an attacker to intercept, view or modify traffic destined for an Incapsula client Web site, and even to divert all traffic for that site to or through a site owned by the attacker. Continue reading

Breach at Hy-Vee Supermarket Chain Tied to Sale of 5M+ Stolen Credit, Debit Cards

August 22, 2019

On Tuesday of this week, one of the more popular underground stores peddling credit and debit card data stolen from hacked merchants announced a blockbuster new sale: More than 5.3 million new accounts belonging to cardholders from 35 U.S. states. Multiple sources now tell KrebsOnSecurity that the card data came from compromised gas pumps, coffee shops and restaurants operated by Hy-Vee, an Iowa-based company that operates a chain of more than 245 supermarkets throughout the Midwestern United States.

Hy-Vee, based in Des Moines, announced on Aug. 14 it was investigating a data breach involving payment processing systems that handle transactions at some Hy-Vee fuel pumps, drive-thru coffee shops and restaurants.

The restaurants affected include Hy-Vee Market Grilles, Market Grille Expresses and Wahlburgers locations that the company owns and operates. Hy-Vee said it was too early to tell when the breach initially began or for how long intruders were inside their payment systems.

But typically, such breaches occur when cybercriminals manage to remotely install malicious software on a retailer’s card-processing systems. This type of point-of-sale malware is capable of copying data stored on a credit or debit card’s magnetic stripe when those cards are swiped at compromised payment terminals. This data can then be used to create counterfeit copies of the cards.

Hy-Vee said it believes the breach does not affect payment card terminals used at its grocery store checkout lanes, pharmacies or convenience stores, as these systems rely on a security technology designed to defeat card-skimming malware.

“These locations have different point-of-sale systems than those located at our grocery stores, drugstores and inside our convenience stores, which utilize point-to-point encryption technology for processing payment card transactions,” Hy-Vee said. “This encryption technology protects card data by making it unreadable. Based on our preliminary investigation, we believe payment card transactions that were swiped or inserted on these systems, which are utilized at our front-end checkout lanes, pharmacies, customer service counters, wine & spirits locations, floral departments, clinics and all other food service areas, as well as transactions processed through Aisles Online, are not involved.”

According to two sources who asked not to be identified for this story — including one at a major U.S. financial institution — the card data stolen from Hy-Vee is now being sold under the code name “Solar Energy,” at the infamous Joker’s Stash carding bazaar.

An ad at the Joker’s Stash carding site for “Solar Energy,” a batch of more than 5 million credit and debit cards sources say was stolen from customers of supermarket chain Hy-Vee.

Hy-Vee said the company’s investigation is continuing.

“We are aware of reports from payment processors and the card networks of payment data being offered for sale and are working with the payment card networks so that they can identify the cards and work with issuing banks to initiate heightened monitoring on accounts,” Hy-Vee spokesperson Tina Pothoff said. Continue reading

Forced Password Reset? Check Your Assumptions

August 21, 2019

Almost weekly now I hear from an indignant reader who suspects a data breach at a Web site they frequent that has just asked the reader to reset their password. Further investigation almost invariably reveals that the password reset demand was not the result of a breach but rather the site’s efforts to identify customers who are reusing passwords from other sites that have already been hacked.

But ironically, many companies taking these proactive steps soon discover that their explanation as to why they’re doing it can get misinterpreted as more evidence of lax security. This post attempts to unravel what’s going on here.

Over the weekend, a follower on Twitter included me in a tweet sent to California-based job search site Glassdoor, which had just sent him the following notice:

The Twitter follower expressed concern about this message, because it suggested to him that in order for Glassdoor to have done what it described, the company would have had to be storing its users’ passwords in plain text. I replied that this was in fact not an indication of storing passwords in plain text, and that many companies are now testing their users’ credentials against lists of hacked credentials that have been leaked and made available online.

The reality is Facebook, Netflix and a number of big-name companies are regularly combing through huge data leak troves for credentials that match those of their customers, and then forcing a password reset for those users. Some are even checking for password re-use on all new account signups.

The idea here is to stymie a massively pervasive problem facing all companies that do business online today: Namely, “credential-stuffing attacks,” in which attackers take millions or even billions of email addresses and corresponding cracked passwords from compromised databases and see how many of them work at other online properties.

So how does the defense against this daily deluge of credential stuffing work? A company employing this strategy will first extract from these leaked credential lists any email addresses that correspond to their current user base.

From there, the corresponding cracked (plain text) passwords are fed into the same process that the company relies upon when users log in: That is, the company feeds those plain text passwords through its own password “hashing” or scrambling routine.

Password hashing is designed to be a one-way function which scrambles a plain text password so that it produces a long string of numbers and letters. Not all hashing methods are created equal, and some of the most commonly used methods — MD5 and SHA-1, for example — can be far less secure than others, depending on how they’re implemented (more on that in a moment). Whatever the hashing method used, it’s the hashed output that gets stored, not the password itself.

Back to the process: If a user’s plain text password from a hacked database matches the output of what a company would expect to see after running it through their own internal hashing process, that user is then prompted to change their password to something truly unique. Continue reading

The Rise of “Bulletproof” Residential Networks

August 19, 2019

Cybercrooks increasingly are anonymizing their malicious traffic by routing it through residential broadband and wireless data connections. Traditionally, those connections have been mainly hacked computers, mobile phones, or home routers. But this story is about so-called “bulletproof residential VPN services” that appear to be built by purchasing or otherwise acquiring discrete chunks of Internet addresses from some of the world’s largest ISPs and mobile data providers.

In late April 2019, KrebsOnSecurity received a tip from an online retailer who’d seen an unusual number of suspicious transactions originating from a series of Internet addresses assigned to a relatively new Internet provider based in Maryland called Residential Networking Solutions LLC.

Now, this in itself isn’t unusual; virtually every provider has the occasional customers who abuse their access for fraudulent purposes. But upon closer inspection, several factors caused me to look more carefully at this company, also known as “Resnet.”

An examination of the IP address ranges assigned to Resnet shows that it maintains an impressive stable of IP blocks — totaling almost 70,000 IPv4 addresses — many of which had until quite recently been assigned to someone else.

Most interestingly, about ten percent of those IPs — more than 7,000 of them — had until late 2018 been under the control of AT&T Mobility. Additionally, the WHOIS registration records for each of these mobile data blocks suggest Resnet has been somehow reselling data services for major mobile and broadband providers, including AT&T, Verizon, and Comcast Cable.

The WHOIS records for one of several networks associated with Residential Networking Solutions LLC.

Drilling down into the tracts of IPs assigned to Resnet’s core network indicates those 7,000+ mobile IP addresses under Resnet’s control were given the label  “Service Provider Corporation” — mostly those beginning with IPs in the range 198.228.x.x.

An Internet search reveals this IP range is administered by the Wireless Data Service Provider Corporation (WDSPC), a non-profit formed in the 1990s to manage IP address ranges that could be handed out to various licensed mobile carriers in the United States.

Back when the WDSPC was first created, there were quite a few mobile wireless data companies. But today the vast majority of the IP space managed by the WDSPC is leased by AT&T Mobility and Verizon Wireless — which have gradually acquired most of their competing providers over the years.

A call to the WDSPC revealed the nonprofit hadn’t leased any new wireless data IP space in more than 10 years. That is, until the organization received a communication at the beginning of this year that it believed was from AT&T, which recommended Resnet as a customer who could occupy some of the company’s mobile data IP address blocks.

“I’m afraid we got duped,” said the person answering the phone at the WDSPC, while declining to elaborate on the precise nature of the alleged duping or the medium that was used to convey the recommendation.

AT&T declined to discuss its exact relationship with Resnet  — or if indeed it ever had one to begin with. It responded to multiple questions about Resnet with a short statement that said, “We have taken steps to terminate this company’s services and have referred the matter to law enforcement.”

Why exactly AT&T would forward the matter to law enforcement remains unclear. But it’s not unheard of for hosting providers to forge certain documents in their quest for additional IP space, and anyone caught doing so via email, phone or fax could be charged with wire fraud, which is a federal offense that carries punishments of up to $500,000 in fines and as much as 20 years in prison.

WHAT IS RESNET?

The WHOIS registration records for Resnet’s main Web site, resnetworking[.]com, are hidden behind domain privacy protection. However, a cursory Internet search on that domain turned up plenty of references to it on Hackforums[.]net, a sprawling community that hosts a seemingly never-ending supply of up-and-coming hackers seeking affordable and anonymous ways to monetize various online moneymaking schemes.

One user in particular — a Hackforums member who goes by the nickname “Profitvolt” — has spent several years advertising resnetworking[.]com and a number of related sites and services, including “unlimited” AT&T 4G/LTE data services, and the immediate availability of more than 1 million residential IPs that he suggested were “perfect for botting, shoe buying.”

The Hackforums user “Profitvolt” advertising residential proxies.

Profitvolt advertises his mobile and residential data services as ideal for anyone who wishes to run “various bots,” or “advertising campaigns.” Those services are meant to provide anonymity when customers are doing things such as automating ad clicks on platforms like Google Adsense and Facebook; generating new PayPal accounts; sneaker bot activity; credential stuffing attacks; and different types of social media spam.

For readers unfamiliar with this term, “shoe botting” or “sneaker bots” refers to the use of automated bot programs and services that aid in the rapid acquisition of limited-release, highly sought-after designer shoes that can then be resold at a profit on secondary markets. All too often, it seems, the people who profit the most in this scheme are using multiple sets of compromised credentials from consumer accounts at online retailers, and/or stolen payment card data.

To say shoe botting has become a thorn in the side of online retailers and regular consumers alike would be a major understatement: A recent State of The Internet Security Report (PDF) from Akamai (an advertiser on this site) noted that such automated bot activity now accounts for almost half of the Internet bandwidth directed at online retailers. The prevalance of shoe botting also might help explain Footlocker‘s recent $100 million investment in goat.com, the largest secondary shoe resale market on the Web.

In other discussion threads, Profitvolt advertises he can rent out an “unlimited number” of so-called “residential proxies,” a term that describes home or mobile Internet connections that can be used to anonymously relay Internet traffic for a variety of dodgy deals.

From a ne’er-do-well’s perspective, the beauty of routing one’s traffic through residential IPs is that few online businesses will bother to block malicious or suspicious activity emanating from them.

That’s because in general the pool of IP addresses assigned to residential or mobile wireless connections cycles intermittently from one user to the next, meaning that blacklisting one residential IP for abuse or malicious activity may only serve to then block legitimate traffic (and e-commerce) from the next user who gets assigned that same IP. Continue reading

Meet Bluetana, the Scourge of Pump Skimmers

August 14, 2019

Bluetana,” a new mobile app that looks for Bluetooth-based payment card skimmers hidden inside gas pumps, is helping police and state employees more rapidly and accurately locate compromised fuel stations across the nation, a study released this week suggests. Data collected in the course of the investigation also reveals some fascinating details that may help explain why these pump skimmers are so lucrative and ubiquitous.

The new app, now being used by agencies in several states, is the brainchild of computer scientists from the University of California San Diego and the University of Illinois Urbana-Champaign, who say they developed the software in tandem with technical input from the U.S. Secret Service (the federal agency most commonly called in to investigate pump skimming rings).

The Bluetooth pump skimmer scanner app ‘Bluetana’ in action.

Gas pumps are a perennial target of skimmer thieves for several reasons. They are usually unattended, and in too many cases a handful of master keys will open a great many pumps at a variety of filling stations.

The skimming devices can then be attached to electronics inside the pumps in a matter of seconds, and because they’re also wired to the pump’s internal power supply the skimmers can operate indefinitely without the need of short-lived batteries.

And increasingly, these pump skimmers are fashioned to relay stolen card data and PINs via Bluetooth wireless technology, meaning the thieves who install them can periodically download stolen card data just by pulling up to a compromised pump and remotely connecting to it from a Bluetooth-enabled mobile device or laptop.

According to the study, some 44 volunteers  — mostly law enforcement officials and state employees — were equipped with Bluetana over a year-long experiment to test the effectiveness of the scanning app.

The researchers said their volunteers collected Bluetooth scans at 1,185 gas stations across six states, and that Bluetana detected a total of 64 skimmers across four of those states. All of the skimmers were later collected by law enforcement, including two that were reportedly missed in manual safety inspections of the pumps six months earlier.

While several other Android-based apps designed to find pump skimmers are already available, the researchers said Bluetana was developed with an eye toward eliminating false-positives that some of these other apps can fail to distinguish.

“Bluetooth technology used in these skimmers are also used for legitimate products commonly seen at and near gas stations such as speed-limit signs, weather sensors and fleet tracking systems,” said Nishant Bhaskar, UC San Diego Ph.D. student and principal author of the study. “These products can be mistaken for skimmers by existing detection apps.” Continue reading

Patch Tuesday, August 2019 Edition

August 13, 2019

Most Microsoft Windows (ab)users probably welcome the monthly ritual of applying security updates about as much as they look forward to going to the dentist: It always seems like you were there just yesterday, and you never quite know how it’s all going to turn out. Fortunately, this month’s patch batch from Redmond is mercifully light, at least compared to last month.

Okay, maybe a trip to the dentist’s office is still preferable. In any case, today is the second Tuesday of the month, which means it’s once again Patch Tuesday (or — depending on your setup and when you’re reading this post — Reboot Wednesday). Microsoft today released patches to fix some 93 vulnerabilities in Windows and related software, 35 of which affect various Server versions of Windows, and another 70 that apply to the Windows 10 operating system.

Although there don’t appear to be any zero-day vulnerabilities fixed this month — i.e. those that get exploited by cybercriminals before an official patch is available — there are several issues that merit attention.

Chief among those are patches to address four moderately terrifying flaws in Microsoft’s Remote Desktop Service, a feature which allows users to remotely access and administer a Windows computer as if they were actually seated in front of the remote computer. Security vendor Qualys says two of these weaknesses can be exploited remotely without any authentication or user interaction.

“According to Microsoft, at least two of these vulnerabilities (CVE-2019-1181 and CVE-2019-1182) can be considered ‘wormable’ and [can be equated] to BlueKeep,” referring to a dangerous bug patched earlier this year that Microsoft warned could be used to spread another WannaCry-like ransomware outbreak. “It is highly likely that at least one of these vulnerabilities will be quickly weaponized, and patching should be prioritized for all Windows systems.”

Fortunately, Remote Desktop is disabled by default in Windows 10, and as such these flaws are more likely to be a threat for enterprises that have enabled the application for various purposes. For those keeping score, this is the fourth time in 2019 Microsoft has had to fix critical security issues with its Remote Desktop service.

For all you Microsoft Edge and Internet Exploiter Explorer users, Microsoft has issued the usual panoply of updates for flaws that could be exploited to install malware after a user merely visits a hacked or booby-trapped Web site. Other equally serious flaws patched in Windows this month could be used to compromise the operating system just by convincing the user to open a malicious file (regardless of which browser the user is running). Continue reading

SEC Investigating Data Leak at First American Financial Corp.

August 12, 2019

The U.S. Securities and Exchange Commission (SEC) is investigating a security failure on the Web site of real estate title insurance giant First American Financial Corp. that exposed more than 885 million personal and financial records tied to mortgage deals going back to 2003, KrebsOnSecurity has learned.

First American Financial Corp.

In May, KrebsOnSecurity broke the news that the Web site for Santa Ana, Calif.-based First American [NYSE:FAFexposed some 885 million documents related to real estate closings over the past 16 years, including bank account numbers and statements, mortgage and tax records, Social Security numbers, wire transaction receipts and drivers license images. No authentication was required to view the documents.

The initial tip on that story came from Ben Shoval, a real estate developer based in Seattle. Shoval said he recently received a letter from the SEC’s enforcement division which stated the agency was investigating the data exposure to determine if First American had violated federal securities laws.

In its letter, the SEC asked Shoval to preserve and share any documents or evidence he had related to the data exposure.

“This investigation is a non-public, fact-finding inquiry,” the letter explained. “The investigation does not mean that we have concluded that anyone has violated the law.”

The SEC declined to comment for this story.

Word of the SEC investigation comes weeks after regulators in New York said they were investigating the company in what could turn out to be the first test of the state’s strict new cybersecurity regulation, which requires financial companies to periodically audit and report on how they protect sensitive data, and provides for fines in cases where violations were reckless or willful. First American also is now the target of a class action lawsuit that alleges it “failed to implement even rudimentary security measures.” Continue reading

iNSYNQ Ransom Attack Began With Phishing Email

August 9, 2019

A ransomware outbreak that hit QuickBooks cloud hosting firm iNSYNQ in mid-July appears to have started with an email phishing attack that snared an employee working in sales for the company, KrebsOnSecurity has learned. It also looks like the intruders spent roughly ten days rooting around iNSYNQ’s internal network to properly stage things before unleashing the ransomware. iNSYNQ ultimately declined to pay the ransom demand, and it is still working to completely restore customer access to files.

Some of this detail came in a virtual “town hall” meeting held August 8, in which iNSYNQ chief executive Elliot Luchansky briefed customers on how it all went down, and what the company is doing to prevent such outages in the future.

A great many iNSYNQ’s customers are accountants, and when the company took its network offline on July 16 in response to the ransomware outbreak, some of those customers took to social media to complain that iNSYNQ was stonewalling them.

“We could definitely have been better prepared, and it’s totally unacceptable,” Luchansky told customers. “I take full responsibility for this. People waiting ridiculous amounts of time for a response is unacceptable.”

By way of explaining iNSYNQ’s initial reluctance to share information about the particulars of the attack early on, Luchansky told customers the company had to assume the intruders were watching and listening to everything iNSYNQ was doing to recover operations and data in the wake of the ransomware outbreak.

“That was done strategically for a good reason,” he said. “There were human beings involved with [carrying out] this attack in real time, and we had to assume they were monitoring everything we could say. And that posed risks based on what we did say publicly while the ransom negotiations were going on. It could have been used in a way that would have exposed customers even more. That put us in a really tough bind, because transparency is something we take very seriously. But we decided it was in our customers’ best interests to not do that.”

A paid ad that comes up prominently when one searches for “insynq” in Google.

Luchansky did not say how much the intruders were demanding, but he mentioned two key factors that informed the company’s decision not to pay up.

“It was a very substantial amount, but we had the money wired and were ready to pay it in cryptocurrency in the case that it made sense to do so,” he told customers. “But we also understood [that paying] would put a target on our heads in the future, and even if we actually received the decryption key, that wasn’t really the main issue here. Because of the quick reaction we had, we were able to contain the encryption part” to roughly 50 percent of customer systems, he said.

Luchansky said the intruders seeded its internal network with MegaCortex, a potent new ransomware strain first spotted just a couple of months ago that is being used in targeted attacks on enterprises. He said the attack appears to have been carefully planned out in advance and executed “with human intervention all the way through.”

“They decided they were coming after us,” he said. “It’s one thing to prepare for these sorts of events but it’s an entirely different experience to deal with first hand.”

According to an analysis of MegaCortex published this week by Accenture iDefense, the crooks behind this ransomware strain are targeting businesses — not home users — and demanding ransom payments in the range of two to 600 bitcoins, which is roughly $20,000 to $5.8 million.

“We are working for profit,” reads the ransom note left behind by the latest version of MegaCortex. “The core of this criminal business is to give back your valuable data in the original form (for ransom of course).”

A portion of the ransom note left behind by the latest version of MegaCortex. Image: Accenture iDefense.

Continue reading