SMS Phishers Harvested Phone Numbers, Shipment Data from UPS Tracking Tool

June 22, 2023
18 Comments

The United Parcel Service (UPS) says fraudsters have been harvesting phone numbers and other information from its online shipment tracking tool in Canada to send highly targeted SMS phishing (a.k.a. “smishing”) messages that spoofed UPS and other top brands. The missives addressed recipients by name, included details about recent orders, and warned that those orders wouldn’t be shipped unless the customer paid an added delivery fee.

In a snail mail letter sent this month to Canadian customers, UPS Canada Ltd. said it is aware that some package recipients have received fraudulent text messages demanding payment before a package can be delivered, and that it has been working with partners in its delivery chain to try to understand how the fraud was occurring.

The recent letter from UPS about SMS phishers harvesting shipment details and phone numbers from its website.

“During that review, UPS discovered a method by which a person who searched for a particular package or misused a package look-up tool could obtain more information about the delivery, potentially including a recipient’s phone number,” the letter reads. “Because this information could be misused by third parties, including potentially in a smishing scheme, UPS has taken steps to limit access to that information.”

The written notice goes on to say UPS believes the data exposure “affected packages for a small group of shippers and some of their customers from February 1, 2022 to April 24, 2023.”

As early as April 2022, KrebsOnSecurity began receiving tips from Canadian readers who were puzzling over why they’d just received one of these SMS phishing messages that referenced information from a recent order they’d legitimately placed at an online retailer.

In March, 2023, a reader named Dylan from British Columbia wrote in to say he’d received one of these shipping fee scam messages not long after placing an order to buy gobs of building blocks directly from Lego.com. The message included his full name, phone number, and postal code, and urged him to click a link to mydeliveryfee-ups[.]info and pay a $1.55 delivery fee that was supposedly required to deliver his Legos.

“From searching the text of this phishing message, I can see that a lot of people have experienced this scam, which is more convincing because of the information the phishing text contains,” Dylan wrote. “It seems likely to me that UPS is leaking information somehow about upcoming deliveries.”

Josh is a reader who works for a company that ships products to Canada, and in early January 2023 he inquired whether there was any information about a breach at UPS Canada.

“We’ve seen many of our customers targeted with a fraudulent UPS text message scheme after placing an order,” Josh said. “A link is provided (often only after the customer responds to the text) which takes you to a captcha page, followed by a fraudulent payment collection page.”

Pivoting on the domain in the smishing message sent to Dylan shows the phishing domain shared an Internet host in Russia [91.215.85-166] with nearly two dozen other smishing related domains, including upsdelivery[.]info, legodelivery[.]info, adidascanadaltd[.]com, crocscanadafee[.]info, refw0234apple[.]info, vista-printcanada[.]info and telus-ca[.]info.

The inclusion of big-name brands in the domains of these UPS smishing campaigns suggests the perpetrators had the ability to focus their lookups on UPS customers who had recently ordered items from specific companies.

Attempts to visit these domains with a web browser failed, but loading them in a mobile device (or in my case, emulating a mobile device using a virtual machine and Developer Tools in Firefox) revealed the first stage of this smishing attack. As Josh mentioned, what first popped up was a CAPTCHA; after the visitor solved the CAPTCHA, they were taken through several more pages that requested the user’s full name, date of birth, credit card number, address, email and phone number.

A smishing website targeting Canadians who recently purchased from Adidas online. The site would only load in a mobile browser.

In April 2022, KrebsOnSecurity heard from Alex, the CEO of a technology company in Canada who asked to leave his last name out of this story. Alex reached out when he began receiving the smishing messages almost immediately after ordering two sets of Airpods directly from Apple’s website.

What puzzled Alex most was that he’d instructed Apple to send the Airpods as a gift to two different people, and less than 24 hours later the phone number he uses for his Apple account received two of the phishing messages, both of which contained salutations that included the names of the people for whom he’d bought Airpods.

“I’d put the recipient as different people on my team, but because it was my phone number on both orders I was the one getting the texts,” Alex explained. “That same day, I got text messages referring to me as two different people, neither of whom were me.” Continue reading →

Why Malware Crypting Services Deserve More Scrutiny

June 21, 2023
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If you operate a cybercrime business that relies on disseminating malicious software, you probably also spend a good deal of time trying to disguise or “crypt” your malware so that it appears benign to antivirus and security products. In fact, the process of “crypting” malware is sufficiently complex and time-consuming that most serious cybercrooks will outsource this critical function to a handful of trusted third parties. This story explores the history and identity behind Cryptor[.]biz, a long-running crypting service that is trusted by some of the biggest names in cybercrime.

Virtually all malware that is deployed for use in data stealing at some point needs to be crypted. This highly technical, laborious process involves iteratively altering the appearance and behavior of a malicious file until it no longer sets off alarm bells when scanned by different antivirus tools.

Experienced malware purveyors understand that if they’re not continuously crypting their malware before sending it out, then a lot more of whatever digital disease they are trying to spread is going to get flagged by security tools. In short, if you are running a cybercrime enterprise and you’re not equipped to handle this crypting process yourself, you probably need to pay someone else to do it for you.

Thanks to the high demand for reliable crypting services, there are countless cybercriminals who’ve hung out their shingles as crypting service providers. However, most of these people do not appear to be very good at what they do, because most are soon out of business.

One standout is Cryptor[.]biz. This service is actually recommended by the purveyors of the RedLine information stealer malware, which is a popular and powerful malware kit that specializes in stealing victim data and is often used to lay the groundwork for ransomware attacks. Cryptor[.]biz also has been recommended to customers of the Vidar information stealer malware family (via the malware’s Telegram support channels). Continue reading →

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CISA Order Highlights Persistent Risk at Network Edge

June 15, 2023
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The U.S. government agency in charge of improving the nation’s cybersecurity posture is ordering all federal agencies to take new measures to restrict access to Internet-exposed networking equipment. The directive comes amid a surge in attacks targeting previously unknown vulnerabilities in widely used security and networking appliances.

Under a new order from the Cybersecurity and Infrastructure Security Agency (CISA), federal agencies will have 14 days to respond to any reports from CISA about misconfigured or Internet-exposed networking equipment. The directive applies to any networking devices — such as firewalls, routers and load balancers — that allow remote authentication or administration.

The order requires federal departments to limit access so that only authorized users on an agency’s local or internal network can reach the management interfaces of these devices. CISA’s mandate follows a slew of recent incidents wherein attackers exploited zero-day flaws in popular networking products to conduct ransomware and cyber espionage attacks on victim organizations.

Earlier today, incident response firm Mandiant revealed that since at least October 2022, Chinese cyber spies have been exploiting a zero-day vulnerability in many email security gateway (ESG) appliances sold by California-based Barracuda Networks to hoover up email from organizations using these devices.

Barracuda was alerted to the exploitation of a zero-day in its products in mid-May, and two days later the company pushed a security update to address the flaw in all affected devices. But last week, Barracuda took the highly unusual step of offering to replace compromised ESGs, evidently in response to malware that altered the systems in such a fundamental way that they could no longer be secured remotely with software updates.

According to Mandiant, a previously unidentified Chinese hacking group was responsible for exploiting the Barracuda flaw, and appeared to be searching through victim organization email records for accounts “belonging to individuals working for a government with political or strategic interest to [China] while this victim government was participating in high-level, diplomatic meetings with other countries.”

When security experts began raising the alarm about a possible zero-day in Barracuda’s products, the Chinese hacking group altered their tactics, techniques and procedures (TTPs) in response to Barracuda’s efforts to contain and remediate the incident, Mandiant found.

Mandiant said the attackers will continue to change their tactics and malware, “especially as network defenders continue to take action against this adversary and their activity is further exposed by the infosec community.”

Meanwhile, this week we learned more details about the ongoing exploitation of a zero-day flaw in a broad range of virtual private networking (VPN) products made by Fortinet — devices many organizations rely on to facilitate remote network access for employees.

On June 11, Fortinet released a half-dozen security updates for its FortiOS firmware, including a weakness that researchers said allows an attacker to run malware on virtually any Fortinet SSL VPN appliance. The researchers found that just being able to reach the management interface for a vulnerable Fortinet SSL VPN appliance was enough to completely compromise the devices.

“This is reachable pre-authentication, on every SSL VPN appliance,” French vulnerability researcher Charles Fol tweeted. “Patch your #Fortigate.” Continue reading →

Microsoft Patch Tuesday, June 2023 Edition

June 13, 2023
29 Comments

Microsoft Corp. today released software updates to fix dozens of security vulnerabilities in its Windows operating systems and other software. This month’s relatively light patch load has another added bonus for system administrators everywhere: It appears to be the first Patch Tuesday since March 2022 that isn’t marred by the active exploitation of a zero-day vulnerability in Microsoft’s products.

June’s Patch Tuesday features updates to plug at least 70 security holes, and while none of these are reported by Microsoft as exploited in-the-wild yet, Redmond has flagged several in particular as “more likely to be exploited.”

Top of the list on that front is CVE-2023-29357, which is a “critical” bug in Microsoft SharePoint Server that can be exploited by an unauthenticated attacker on the same network. This SharePoint flaw earned a CVSS rating of 9.8 (10.0 is the most dangerous).

“An attacker able to gain admin access to an internal SharePoint server could do a lot of harm to an organization,” said Kevin Breen, director of cyber threat research at Immersive Labs. “Gaining access to sensitive and privileged documents, stealing and deleting documents as part of a ransomware attack or replacing real documents with malicious copies to further infect users in the organization.”

There are at least three other vulnerabilities fixed this month that earned a collective 9.8 CVSS score, and they all concern a widely-deployed component called the Windows Pragmatic General Multicast (PGM), which is used for delivering multicast data — such as video streaming or online gaming.

Security firm Action1 says all three bugs (CVE-2023-32015, CVE-2023-32014, and CVE-2023-29363) can be exploited over the network without requiring any privileges or user interaction, and affected systems include all versions of Windows Server 2008 and later, as well as Windows 10 and later. Continue reading →

Barracuda Urges Replacing — Not Patching — Its Email Security Gateways

June 8, 2023
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It’s not often that a zero-day vulnerability causes a network security vendor to urge customers to physically remove and decommission an entire line of affected hardware — as opposed to just applying software updates. But experts say that is exactly what transpired this week with Barracuda Networks, as the company struggled to combat a sprawling malware threat which appears to have undermined its email security appliances in such a fundamental way that they can no longer be safely updated with software fixes.

The Barracuda Email Security Gateway (ESG) 900 appliance.

Campbell, Calif. based Barracuda said it hired incident response firm Mandiant on May 18 after receiving reports about unusual traffic originating from its Email Security Gateway (ESG) devices, which are designed to sit at the edge of an organization’s network and scan all incoming and outgoing email for malware.

On May 19, Barracuda identified that the malicious traffic was taking advantage of a previously unknown vulnerability in its ESG appliances, and on May 20 the company pushed a patch for the flaw to all affected appliances (CVE-2023-2868).

In its security advisory, Barracuda said the vulnerability existed in the Barracuda software component responsible for screening attachments for malware. More alarmingly, the company said it appears attackers first started exploiting the flaw in October 2022.

But on June 6, Barracuda suddenly began urging its ESG customers to wholesale rip out and replace — not patch — affected appliances.

“Impacted ESG appliances must be immediately replaced regardless of patch version level,” the company’s advisory warned. “Barracuda’s recommendation at this time is full replacement of the impacted ESG.”

In a statement, Barracuda said it will be providing the replacement product to impacted customers at no cost, and that not all ESG appliances were compromised.

“No other Barracuda product, including our SaaS email solutions, were impacted by this vulnerability,” the company said. “If an ESG appliance is displaying a notification in the User Interface, the ESG appliance had indicators of compromise. If no notification is displayed, we have no reason to believe that the appliance has been compromised at this time.”

Nevertheless, the statement says that “out of an abundance of caution and in furtherance of our containment strategy, we recommend impacted customers replace their compromised appliance.”

“As of June 8, 2023, approximately 5% of active ESG appliances worldwide have shown any evidence of known indicators of compromise due to the vulnerability,” the statement continues. “Despite deployment of additional patches based on known IOCs, we continue to see evidence of ongoing malware activity on a subset of the compromised appliances. Therefore, we would like customers to replace any compromised appliance with a new unaffected device.”

Rapid7‘s Caitlin Condon called this remarkable turn of events “fairly stunning,” and said there appear to be roughly 11,000 vulnerable ESG devices still connected to the Internet worldwide.

“The pivot from patch to total replacement of affected devices is fairly stunning and implies the malware the threat actors deployed somehow achieves persistence at a low enough level that even wiping the device wouldn’t eradicate attacker access,” Condon wrote. Continue reading →

Service Rents Email Addresses for Account Signups

June 6, 2023
5 Comments

One of the most expensive aspects of any cybercriminal operation is the time and effort it takes to constantly create large numbers of new throwaway email accounts. Now a new service offers to help dramatically cut costs associated with large-scale spam and account creation campaigns, by paying people to sell their email account credentials and letting customers temporarily rent access to a vast pool of established accounts at major providers.

The service in question — kopeechka[.]store — is perhaps best described as a kind of unidirectional email confirmation-as-a-service that promises to “save your time and money for successfully registering multiple accounts.”

“Are you working on large volumes and are costs constantly growing?” Kopeechka’s website asks. “Our service will solve all your problems.”

As a customer of this service, you don’t get full access to the email inboxes you are renting. Rather, you configure your botnet or spam machine to make an automated application programming interface (API) call to the Kopeechka service, which responds with a working email address at an email provider of your choosing.

Once you’ve entered the supplied email address into the new account registration page at some website or service, you tell Kopeechka which service or website you’re expecting an account confirmation link from, and they will then forward any new messages matching that description to your Kopeechka account panel.

Ensuring that customers cannot control inboxes rented through the service means that Kopeechka can rent the same email address to multiple customers (at least until that email address has been used to register accounts at most of the major online services).

Kopeechka also has multiple affiliate programs, including one that pays app developers for embedding Kopeechka’s API in their software. However, far more interesting is their program for rewarding people who choose to sell Kopeechka usernames and passwords for working email addresses.

Kopeechka means “penny” in Russian, which is generous verbiage (and coinage) for a service that charges a tiny fraction of a penny for access to account confirmation links. Their pricing fluctuates slightly based on which email provider you choose, but a form on the service’s homepage says a single confirmation message from apple.com to outlook.com costs .07 rubles, which is currently equal to about $0.00087 dollars.

The pricing for Kopeechka works out to about a fraction of a penny per confirmation message.

“Emails can be uploaded to us for sale, and you will receive a percentage of purchases %,” the service explains. “You upload 1 mailbox of a certain domain, discuss percentage with our technical support (it depends on the liquidity of the domain and the number of downloaded emails).”

We don’t have to look very far for examples of Kopeechka in action. In May, KrebsOnSecurity interviewed a Russian spammer named “Quotpw“ who was mass-registering accounts on the social media network Mastodon in order to conduct a series of huge spam campaigns advertising scam cryptocurrency investment platforms.

Much of the fodder for that story came from Renaud Chaput, a freelance programmer working on modernizing and scaling the Mastodon project infrastructure — including joinmastodon.org, mastodon.online, and mastodon.social. Chaput told KrebsOnSecurity that his team was forced to temporarily halt all new registrations for these communities last month after the number of new registrations from Quotpw’s spam campaign started to overwhelm their systems.

“We suddenly went from like three registrations per minute to 900 a minute,” Chaput said. “There was nothing in the Mastodon software to detect that activity, and the protocol is not designed to handle this.”

After that story ran, Chaput said he discovered that the computer code powering Quotpw’s spam botnet (which has since been released as open source) contained an API call to Kopeechka’s service.

“It allows them to pool many bot-created or compromised emails at various providers and offer them to cyber criminals,” Chaput said of Kopeechka. “This is what they used to create thousands of valid Hotmail (and other) addresses when spamming on Mastodon. If you look at the code, it’s really well done with a nice API that forwards you the confirmation link that you can then fake click with your botnet.” Continue reading →

Ask Fitis, the Bear: Real Crooks Sign Their Malware

June 1, 2023
13 Comments

Code-signing certificates are supposed to help authenticate the identity of software publishers, and provide cryptographic assurance that a signed piece of software has not been altered or tampered with. Both of these qualities make stolen or ill-gotten code-signing certificates attractive to cybercriminal groups, who prize their ability to add stealth and longevity to malicious software. This post is a deep dive on “Megatraffer,” a veteran Russian hacker who has practically cornered the underground market for malware focused code-signing certificates since 2015.

One of Megatraffer’s ads on an English-language cybercrime forum.

A review of Megatraffer’s posts on Russian crime forums shows this user began peddling individual stolen code-signing certs in 2015 on the Russian-language forum Exploit, and soon expanded to selling certificates for cryptographically signing applications and files designed to run in Microsoft Windows, Java, Adobe AIR, Mac and Microsoft Office.

Megatraffer explained that malware purveyors need a certificate because many antivirus products will be far more interested in unsigned software, and because signed files downloaded from the Internet don’t tend to get blocked by security features built into modern web browsers. Additionally, newer versions of Microsoft Windows will complain with a bright yellow or red alert message if users try to install a program that is not signed.

“Why do I need a certificate?” Megatraffer asked rhetorically in their Jan. 2016 sales thread on Exploit. “Antivirus software trusts signed programs more. For some types of software, a digital signature is mandatory.”

At the time, Megatraffer was selling unique code-signing certificates for $700 apiece, and charging more than twice that amount ($1,900) for an “extended validation” or EV code-signing cert, which is supposed to only come with additional identity vetting of the certificate holder. According to Megatraffer, EV certificates were a “must-have” if you wanted to sign malicious software or hardware drivers that would reliably work in newer Windows operating systems.

Part of Megatraffer’s ad. Image: Ke-la.com.

Megatraffer has continued to offer their code-signing services across more than a half-dozen other Russian-language cybercrime forums, mostly in the form of sporadically available EV and non-EV code-signing certificates from major vendors like Thawte and Comodo.

More recently, it appears Megatraffer has been working with ransomware groups to help improve the stealth of their malware. Shortly after Russia invaded Ukraine in February 2022, someone leaked several years of internal chat logs from the Conti ransomware gang, and those logs show Megatraffer was working with the group to help code-sign their malware between July and October 2020. Continue reading →

Discord Admins Hacked by Malicious Bookmarks

May 30, 2023
11 Comments

A number of Discord communities focused on cryptocurrency have been hacked this past month after their administrators were tricked into running malicious Javascript code disguised as a Web browser bookmark.

This attack involves malicious Javascript that is added to one’s browser by dragging a component from a web page to one’s browser bookmarks.

According to interviews with victims, several of the attacks began with an interview request from someone posing as a reporter for a crypto-focused news outlet online. Those who take the bait are sent a link to a Discord server that appears to be the official Discord of the crypto news site, where they are asked to complete a verification step to validate their identity.

As shown in this Youtube video, the verification process involves dragging a button from the phony crypto news Discord server to the bookmarks bar in one’s Web browser. From there, the visitor is instructed to go back to discord.com and then click the new bookmark to complete the verification process.

However, the bookmark is actually a clever snippet of Javascript that quietly grabs the user’s Discord token and sends it to the scammer’s website. The attacker then loads the stolen token into their own browser session and (usually late at night after the admins are asleep) posts an announcement in the targeted Discord about an exclusive “airdrop,” “NFT mint event” or some other potential money making opportunity for the Discord members.

The unsuspecting Discord members click the link provided by the compromised administrator account, and are asked to connect their crypto wallet to the scammer’s site, where it asks for unlimited spend approvals on their tokens, and subsequently drains the balance of any valuable accounts.

Meanwhile, anyone in the compromised Discord channel who notices the scam and replies is banned, and their messages are deleted by the compromised admin account.

Nicholas Scavuzzo is an associate at Ocean Protocol, which describes itself as an “open-source protocol that aims to allow businesses and individuals to exchange and monetize data and data-based services.” On May 22, an administrator for Ocean Protocol’s Discord server clicked a link in a direct message from a community member that prompted them to prove their identity by dragging a link to their bookmarks.

Scavuzzo, who is based in Maine, said the attackers waited until around midnight in his timezone time before using the administrator’s account to send out an unauthorized message about a new Ocean airdrop.

Scavuzzo said the administrator’s account was hijacked even though she had multi-factor authentication turned on.

“A CAPTCHA bot that allows Discord cookies to be accessed by the person hosting the CAPTCHA,” was how Scavuzzo described the attack. “I’ve seen all kinds of crypto scams, but I’ve never seen one like this.”

In this conversation, “Ana | Ocean” is a compromised Discord server administrator account promoting a phony airdrop.

Importantly, the stolen token only works for the attackers as long as its rightful owner doesn’t log out and back in, or else change their credentials.

Assuming the administrator can log in, that is. In Ocean’s case, one of the first things the intruders did once they swiped the administrator’s token was change the server’s access controls and remove all core Ocean team members from the server.

Fortunately for Ocean, Scavuzzo was able to reach the operator of the server that hosts the Discord channel, and have the channel’s settings reverted back to normal.

“Thankfully, we are a globally distributed team, so we have people awake at all hours,” Scavuzzo said, noting that Ocean is not aware of any Discord community members who fell for the phony airdrop offer, which was live for about 30 minutes. “This could have been a lot worse.”

On May 26, Aura Network reported on Twitter that its Discord server was compromised in a phishing attack that resulted in the deletion of Discord channels and the dissemination of fake Aura Network Airdrop Campaign links.

On May 27, Nahmii — a cryptocurrency technology based on the Ethereum blockchain — warned on Twitter that one of its community moderators on Discord was compromised and posting fake airdrop details.

On May 9, MetrixCoin reported that its Discord server was hacked, with fake airdrop details pushed to all users. Continue reading →

Phishing Domains Tanked After Meta Sued Freenom

May 26, 2023
12 Comments

The number of phishing websites tied to domain name registrar Freenom dropped precipitously in the months surrounding a recent lawsuit from social networking giant Meta, which alleged the free domain name provider has a long history of ignoring abuse complaints about phishing websites while monetizing traffic to those abusive domains.

The volume of phishing websites registered through Freenom dropped considerably since the registrar was sued by Meta. Image: Interisle Consulting.

Freenom is the domain name registry service provider for five so-called “country code top level domains” (ccTLDs), including .cf for the Central African Republic; .ga for Gabon; .gq for Equatorial Guinea; .ml for Mali; and .tk for Tokelau.

Freenom has always waived the registration fees for domains in these country-code domains, but the registrar also reserves the right to take back free domains at any time, and to divert traffic to other sites — including adult websites. And there are countless reports from Freenom users who’ve seen free domains removed from their control and forwarded to other websites.

By the time Meta initially filed its lawsuit in December 2022, Freenom was the source of well more than half of all new phishing domains coming from country-code top-level domains. Meta initially asked a court to seal its case against Freenom, but that request was denied. Meta withdrew its December 2022 lawsuit and re-filed it in March 2023.

“The five ccTLDs to which Freenom provides its services are the TLDs of choice for cybercriminals because Freenom provides free domain name registration services and shields its customers’ identity, even after being presented with evidence that the domain names are being used for illegal purposes,” Meta’s complaint charged. “Even after receiving notices of infringement or phishing by its customers, Freenom continues to license new infringing domain names to those same customers.”

Meta pointed to research from Interisle Consulting Group, which discovered in 2021 and again last year that the five ccTLDs operated by Freenom made up half of the Top Ten TLDs most abused by phishers.

Interisle partner Dave Piscitello said something remarkable has happened in the months since the Meta lawsuit.

“We’ve observed a significant decline in phishing domains reported in the Freenom commercialized ccTLDs in months surrounding the lawsuit,” Piscitello wrote on Mastodon. “Responsible for over 60% of phishing domains reported in November 2022, Freenom’s percentage has dropped to under 15%.”

Interisle collects data from 12 major blocklists for spam, malware, and phishing, and it receives phishing-specific data from Spamhaus, Phishtank, OpenPhish and the APWG Ecrime Exchange. The company publishes historical data sets quarterly, both on malware and phishing.

Piscitello said it’s too soon to tell the full impact of the Freenom lawsuit, noting that Interisle’s sources of spam and phishing data all have different policies about when domains are removed from their block lists.

“One of the things we don’t have visibility into is how each of the blocklists determine to remove a URL from their lists,” he said. “Some of them time out [listed domains] after 14 days, some do it after 30, and some keep them forever.”

Freenom did not respond to requests for comment.

This is the second time in as many years that a lawsuit by Meta against a domain registrar has disrupted the phishing industry. In March 2020, Meta sued domain registrar giant Namecheap, alleging cybersquatting and trademark infringement.

The two parties settled the matter in April 2022. While the terms of that settlement have not been disclosed, new phishing domains registered through Namecheap declined more than 50 percent the following quarter, Interisle found.

Phishing attacks using websites registered through Namecheap, before and after the registrar settled a lawsuit with Meta. Image: Interisle Consulting.

Continue reading →

Interview With a Crypto Scam Investment Spammer

May 22, 2023
15 Comments

Social networks are constantly battling inauthentic bot accounts that send direct messages to users promoting scam cryptocurrency investment platforms. What follows is an interview with a Russian hacker responsible for a series of aggressive crypto spam campaigns that recently prompted several large Mastodon communities to temporarily halt new registrations. According to the hacker, their spam software has been in private use until the last few weeks, when it was released as open source code.

Renaud Chaput is a freelance programmer working on modernizing and scaling the Mastodon project infrastructure — including joinmastodon.org, mastodon.online, and mastodon.social. Chaput said that on May 4, 2023, someone unleashed a spam torrent targeting users on these Mastodon communities via “private mentions,” a kind of direct messaging on the platform.

The messages said recipients had earned an investment credit at a cryptocurrency trading platform called moonxtrade[.]com. Chaput said the spammers used more than 1,500 Internet addresses across 400 providers to register new accounts, which then followed popular accounts on Mastodon and sent private mentions to the followers of those accounts.

Since then, the same spammers have used this method to advertise more than 100 different crypto investment-themed domains. Chaput said that at one point this month the volume of bot accounts being registered for the crypto spam campaign started overwhelming the servers that handle new signups at Mastodon.social.

“We suddenly went from like three registrations per minute to 900 a minute,” Chaput said. “There was nothing in the Mastodon software to detect that activity, and the protocol is not designed to handle this.”

One of the crypto investment scam messages promoted in the spam campaigns on Mastodon this month.

Seeking to gain a temporary handle on the spam wave, Chaput said he briefly disabled new account registrations on mastodon.social and mastondon.online. Shortly after that, those same servers came under a sustained distributed denial-of-service (DDoS) attack.

Chaput said whoever was behind the DDoS was definitely not using point-and-click DDoS tools, like a booter or stresser service.

“This was three hours non-stop, 200,000 to 400,000 requests per second,” Chaput said of the DDoS. “At first, they were targeting one path, and when we blocked that they started to randomize things. Over three hours the attack evolved several times.”

Chaput says the spam waves have died down since they retrofitted mastodon.social with a CAPTCHA, those squiggly letter and number combinations designed to stymie automated account creation tools. But he’s worried that other Mastodon instances may not be as well-staffed and might be easy prey for these spammers.

“We don’t know if this is the work of one person, or if this is [related to] software or services being sold to others,” Chaput told KrebsOnSecurity. “We’re really impressed by the scale of it — using hundreds of domains and thousands of Microsoft email addresses.”

Chaput said a review of their logs indicates many of the newly registered Mastodon spam accounts were registered using the same 0auth credentials, and that a domain common to those credentials was quot[.]pw.

A DIRECT QUOT

The domain quot[.]pw has been registered and abandoned by several parties since 2014, but the most recent registration data available through DomainTools.com shows it was registered in March 2020 to someone in Krasnodar, Russia with the email address edgard011012@gmail.com.

This email address is also connected to accounts on several Russian cybercrime forums, including “__edman__,” who had a history of selling “logs” — large amounts of data stolen from many bot-infected computers — as well as giving away access to hacked Internet of Things (IoT) devices.

In September 2018, a user by the name “ципа” (phonetically “Zipper” in Russian) registered on the Russian hacking forum Lolzteam using the edgard0111012@gmail.com address. In May 2020, Zipper told another Lolzteam member that quot[.]pw was their domain. That user advertised a service called “Quot Project” which said they could be hired to write programming scripts in Python and C++.

“I make Telegram bots and other rubbish cheaply,” reads one February 2020 sales thread from Zipper.

Quotpw/Ahick/Edgard/ципа advertising his coding services in this Google-translated forum posting.

Clicking the “open chat in Telegram” button on Zipper’s Lolzteam profile page launched a Telegram instant message chat window where the user Quotpw responded almost immediately. Asked if they were aware their domain was being used to manage a spam botnet that was pelting Mastodon instances with crypto scam spam, Quotpw confirmed the spam was powered by their software.

“It was made for a limited circle of people,” Quotpw said, noting that they recently released the bot software as open source on GitHub.

Quotpw went on to say the spam botnet was powered by well more than the hundreds of IP addresses tracked by Chaput, and that these systems were mostly residential proxies. A residential proxy generally refers to a computer or mobile device running some type of software that enables the system to be used as a pass-through for Internet traffic from others.

Very often, this proxy software is installed surreptitiously, such as through a “Free VPN” service or mobile app. Residential proxies also can refer to households protected by compromised home routers running factory-default credentials or outdated firmware.

Quotpw maintains they have earned more than $2,000 sending roughly 100,000 private mentions to users of different Mastodon communities over the past few weeks. Quotpw said their conversion rate for the same bot-powered direct message spam on Twitter is usually much higher and more profitable, although they conceded that recent adjustments to Twitter’s anti-bot CAPTCHA have put a crimp in their Twitter earnings.

“My partners (I’m programmer) lost time and money while ArkoseLabs (funcaptcha) introduced new precautions on Twitter,” Quotpw wrote in a Telegram reply. “On Twitter, more spam and crypto scam.”

Asked whether they felt at all conflicted about spamming people with invitations to cryptocurrency scams, Quotpw said in their hometown “they pay more for such work than in ‘white’ jobs” — referring to legitimate programming jobs that don’t involve malware, botnets, spams and scams.

“Consider salaries in Russia,” Quotpw said. “Any spam is made for profit and brings illegal money to spammers.” Continue reading →