A Croatian national has been arrested for allegedly operating NetWire, a Remote Access Trojan (RAT) marketed on cybercrime forums since 2012 as a stealthy way to spy on infected systems and siphon passwords. The arrest coincided with a seizure of the NetWire sales website by the U.S. Federal Bureau of Investigation (FBI). While the defendant in this case hasn’t yet been named publicly, the NetWire website has been leaking information about the likely true identity and location of its owner for the past 11 years.

Typically installed by booby-trapped Microsoft Office documents and distributed via email, NetWire is a multi-platform threat that is capable of targeting not only Microsoft Windows machines but also Android, Linux and Mac systems.

NetWire’s reliability and relatively low cost ($80-$140 depending on features) has made it an extremely popular RAT on the cybercrime forums for years, and NetWire infections consistently rank among the top 10 most active RATs in use.

NetWire has been sold openly on the same website since 2012: worldwiredlabs[.]com. That website now features a seizure notice from the U.S. Department of Justice, which says the domain was taken as part of “a coordinated law enforcement action taken against the NetWire Remote Access Trojan.”

“As part of this week’s law enforcement action, authorities in Croatia on Tuesday arrested a Croatian national who allegedly was the administrator of the website,” reads a statement by the U.S. Department of Justice today. “This defendant will be prosecuted by Croatian authorities. Additionally, law enforcement in Switzerland on Tuesday seized the computer server hosting the NetWire RAT infrastructure.”

Neither the DOJ’s statement nor a press release on the operation published by Croatian authorities mentioned the name of the accused. But it’s fairly remarkable that it has taken so long for authorities in the United States and elsewhere to move against NetWire and its alleged proprietor, given that the RAT’s author apparently did very little to hide his real-life identity.

The WorldWiredLabs website first came online in February 2012 using a dedicated host with no other domains. The site’s true WHOIS registration records have always been hidden by privacy protection services, but there are plenty of clues in historical Domain Name System (DNS) records for WorldWiredLabs that point in the same direction.

In October 2012, the WorldWiredLabs domain moved to another dedicated server at the Internet address 198.91.90.7, which was home to just one other domain: printschoolmedia[.]org, also registered in 2012.

According to DomainTools.com, printschoolmedia[.]org was registered to a Mario Zanko in Zapresic, Croatia, and to the email address zankomario@gmail.com. DomainTools further shows this email address was used to register one other domain in 2012: wwlabshosting[.]com, also registered to Mario Zanko from Croatia.

A review of DNS records for both printschoolmedia[.]org and wwlabshosting[.]com shows that while these domains were online they both used the DNS name server ns1.worldwiredlabs[.]com. No other domains have been recorded using that same name server.

DNS records for worldwiredlabs[.]com also show the site forwarded incoming email to the address tommaloney@ruggedinbox.com. Constella Intelligence, a service that indexes information exposed by public database leaks, shows this email address was used to register an account at the clothing retailer romwe.com, using the password “123456xx.”

Running a reverse search on this password in Constella Intelligence shows there are more than 450 email addresses known to have used this credential, and two of those are zankomario@gmail.com and zankomario@yahoo.com.

A search on zankomario@gmail.com in Skype returns three results, including the account name “Netwire” and the username “Dugidox,” and another for a Mario Zanko (username zanko.mario).

Dugidox corresponds to the hacker handle most frequently associated with NetWire sales and support discussion threads on multiple cybercrime forums over the years.

Constella ties dugidox@gmail.com to a number of website registrations, including the Dugidox handle on BlackHatWorld and HackForums, and to IP addresses in Croatia for both. Constella also shows the email address zankomario@gmail.com used the password “dugidox2407.”

In 2010, someone using the email address dugidox@gmail.com registered the domain dugidox[.]com. The WHOIS registration records for that domain list a “Senela Eanko” as the registrant, but the address used was the same street address in Zapresic that appears in the WHOIS records for printschoolmedia[.]org, which is registered in Mr. Zanco’s name.

Prior to the demise of Google+, the email address dugidox@gmail.com mapped to an account with the nickname “Netwire wwl.” The dugidox email also was tied to a Facebook account (mario.zanko3), which featured check-ins and photos from various places in Croatia.

That Facebook profile is no longer active, but back in January 2017, the administrator of WorldWiredLabs posted that he was considering adding certain Android mobile functionality to his service. Three days after that, the Mario.Zank3 profile posted a photo saying he was selected for an Android instruction course — with his dugidox email in the photo, naturally.

Incorporation records from the U.K.’s Companies House shows that in 2017 Mr. Zanko became an officer in a company called Godbex Solutions LTD. A Youtube video invoking this corporate name describes Godbex as a “next generation platform” for exchanging gold and cryptocurrencies.

The U.K. Companies House records show Godbex was dissolved in 2020. It also says Mr. Zanko was born in July 1983, and lists his occupation as “electrical engineer.”

Mr. Zanko did not respond to multiple requests for comment.

The domain name registrar Freenom, whose free domain names have long been a draw for spammers and phishers, has stopped allowing new domain name registrations. The move comes just days after the Dutch registrar was sued by Meta, which alleges the company ignores abuse complaints about phishing websites while monetizing traffic to those abusive domains.

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, presumably as a way to encourage users to pay for related services, such as registering a .com or .net domain, for which Freenom does charge a fee.

On March 3, 2023, social media giant Meta sued Freenom in a Northern California court, alleging cybersquatting violations and trademark infringement. The lawsuit also seeks information about the identities of 20 different “John Does” — Freenom customers that Meta says have been particularly active in phishing attacks against Facebook, Instagram, and WhatsApp users.

The lawsuit points to a 2021 study (PDF) on the abuse of domains conducted for the European Commission, which discovered that those ccTLDs operated by Freenom made up five of the Top Ten TLDs most abused by phishers.

“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,” the complaint charges. “Even after receiving notices of infringement or phishing by its customers, Freenom continues to license new infringing domain names to those same customers.”

Meta further alleges that “Freenom has repeatedly failed to take appropriate steps to investigate and respond appropriately to reports of abuse,” and that it monetizes the traffic from infringing domains by reselling them and by adding “parking pages” that redirect visitors to other commercial websites, websites with pornographic content, and websites used for malicious activity like phishing.

Freenom has not yet responded to requests for comment. But attempts to register a domain through the company’s website as of publication time generated an error message that reads:

“Because of technical issues the Freenom application for new registrations is temporarily out-of-order. Please accept our apologies for the inconvenience. We are working on a solution and hope to resume operations shortly. Thank you for your understanding.”

Although Freenom is based in The Netherlands, some of its other sister companies named as defendants in the lawsuit names are incorporated in the United States.

Meta initially filed this lawsuit in December 2022, but it asked the court to seal the case, which would have restricted public access to court documents in the dispute. That request was denied, and Meta amended and re-filed the lawsuit last week.

According to Meta, this isn’t just a case of another domain name registrar ignoring abuse complaints because it’s bad for business. The lawsuit alleges that the owners of Freenom “are part of a web of companies created to facilitate cybersquatting, all for the benefit of Freenom.”

“On information and belief, one or more of the ccTLD Service Providers, ID Shield, Yoursafe, Freedom Registry, Fintag, Cervesia, VTL, Joost Zuurbier Management Services B.V., and Doe Defendants were created to hide assets, ensure unlawful activity including cybersquatting and phishing goes undetected, and to further the goals of Freenom,” Meta charged.

It remains unclear why Freenom has stopped allowing domain registration, but it could be that the company was recently the subject of some kind of disciplinary action by the Internet Corporation for Assigned Names and Numbers (ICANN), the nonprofit entity which oversees the domain registrars.

In June 2015, ICANN suspended Freenom’s ability to create new domain names or initiate inbound transfers of domain names for 90 days. According to Meta, the suspension was premised on ICANN’s determination that Freenom “has engaged in a pattern and practice of trafficking in or use of domain names identical or confusingly similar to a trademark or service mark of a third party in which the Registered Name Holder has no rights or legitimate interest.”

ICANN has not yet responded to requests for comment.

A copy of the amended complaint against Freenom, et. al, is available here (PDF).

The Biden administration today issued its vision for beefing up the nation’s collective cybersecurity posture, including calls for legislation establishing liability for software products and services that are sold with little regard for security. The White House’s new national cybersecurity strategy also envisions a more active role by cloud providers and the U.S. military in disrupting cybercriminal infrastructure, and it names China as the single biggest cyber threat to U.S. interests.

The strategy says the White House will work with Congress and the private sector to develop legislation that would prevent companies from disavowing responsibility for the security of their software products or services.

Coupled with this stick would be a carrot: An as-yet-undefined “safe harbor framework” that would lay out what these companies could do to demonstrate that they are making cybersecurity a central concern of their design and operations.

“Any such legislation should prevent manufacturers and software publishers with market power from fully disclaiming liability by contract, and establish higher standards of care for software in specific high-risk scenarios,” the strategy explains. “To begin to shape standards of care for secure software development, the Administration will drive the development of an adaptable safe harbor framework to shield from liability companies that securely develop and maintain their software products and services.”

Brian Fox, chief technology officer and founder of the software supply chain security firm Sonatype, called the software liability push a landmark moment for the industry.

“Market forces are leading to a race to the bottom in certain industries, while contract law allows software vendors of all kinds to shield themselves from liability,” Fox said. “Regulations for other industries went through a similar transformation, and we saw a positive result — there’s now an expectation of appropriate due care, and accountability for those who fail to comply. Establishing the concept of safe harbors allows the industry to mature incrementally, leveling up security best practices in order to retain a liability shield, versus calling for sweeping reform and unrealistic outcomes as previous regulatory attempts have.”

THE MOST ACTIVE, PERSISTENT THREAT

In 2012 (approximately three national cyber strategies ago), then director of the U.S. National Security Agency (NSA) Keith Alexander made headlines when he remarked that years of successful cyber espionage campaigns from Chinese state-sponsored hackers represented “the greatest transfer of wealth in history.”

The document released today says the People’s Republic of China (PRC) “now presents the broadest, most active, and most persistent threat to both government and private sector networks,” and says China is “the only country with both the intent to reshape the international order and, increasingly, the economic, diplomatic, military, and technological power to do so.”

Many of the U.S. government’s efforts to restrain China’s technology prowess involve ongoing initiatives like the CHIPS Act, a new law signed by President Biden last year that sets aside more than $50 billion to expand U.S.-based semiconductor manufacturing and research and to make the U.S. less dependent on foreign suppliers; the National Artificial Intelligence Initiative; and the National Strategy to Secure 5G.

As the maker of most consumer gizmos with a computer chip inside, China is also the source of an incredible number of low-cost Internet of Things (IoT) devices that are not only poorly secured, but are probably more accurately described as insecure by design.

The Biden administration said it would continue its previously announced plans to develop a system of labeling that could be applied to various IoT products and give consumers some idea of how secure the products may be. But it remains unclear how those labels might apply to products made by companies outside of the United States.

FIGHTING BADNESS IN THE CLOUD

One could convincingly make the case that the world has witnessed yet another historic transfer of wealth and trade secrets over the past decade — in the form of ransomware and data ransom attacks by Russia-based cybercriminal syndicates, as well as Russian intelligence agency operations like the U.S. government-wide Solar Winds compromise.

On the ransomware front, the White House strategy seems to focus heavily on building the capability to disrupt the digital infrastructure used by adversaries that are threatening vital U.S. cyber interests. The document points to the 2021 takedown of the Emotet botnet — a cybercrime machine that was heavily used by multiple Russian ransomware groups — as a model for this activity, but says those disruptive operations need to happen faster and more often.

To that end, the Biden administration says it will expand the capacity of the National Cyber Investigative Joint Task Force (NCIJTF), the primary federal agency for coordinating cyber threat investigations across law enforcement agencies, the intelligence community, and the Department of Defense.

“To increase the volume and speed of these integrated disruption campaigns, the Federal Government must further develop technological and organizational platforms that enable continuous, coordinated operations,” the strategy observes. “The NCIJTF will expand its capacity to coordinate takedown and disruption campaigns with greater speed, scale, and frequency. Similarly, DoD and the Intelligence Community are committed to bringing to bear their full range of complementary authorities to disruption campaigns.”

The strategy anticipates the U.S. government working more closely with cloud and other Internet infrastructure providers to quickly identify malicious use of U.S.-based infrastructure, share reports of malicious use with the government, and make it easier for victims to report abuse of these systems.

“Given the interest of the cybersecurity community and digital infrastructure owners and operators in continuing this approach, we must sustain and expand upon this model so that collaborative disruption operations can be carried out on a continuous basis,” the strategy argues. “Threat specific collaboration should take the form of nimble, temporary cells, comprised of a small number of trusted operators, hosted and supported by a relevant hub. Using virtual collaboration platforms, members of the cell would share information bidirectionally and work rapidly to disrupt adversaries.”

But here, again, there is a carrot-and-stick approach: The administration said it is taking steps to implement Executive Order (EO) 13984 –issued by the Trump administration in January 2021 — which requires cloud providers to verify the identity of foreign persons using their services.

“All service providers must make reasonable attempts to secure the use of their infrastructure against abuse or other criminal behavior,” the strategy states. “The Administration will prioritize adoption and enforcement of a risk-based approach to cybersecurity across Infrastructure-as-a-Service providers that addresses known methods and indicators of malicious activity including through implementation of EO 13984.”

Ted Schlein, founding partner of the cybersecurity venture capital firm Ballistic Ventures, said how this gets implemented will determine whether it can be effective.

“Adversaries know the NSA, which is the elite portion of the nation’s cyber defense, cannot monitor U.S.-based infrastructure, so they just use U.S.-based cloud infrastructure to perpetrate their attacks,” Schlein said. “We have to fix this. I believe some of this section is a bit pollyannaish, as it assumes a bad actor with a desire to do a bad thing will self-identify themselves, as the major recommendation here is around KYC (‘know your customer’).”

INSURING THE INSURERS

One brief but interesting section of the strategy titled “Explore a Federal Cyber Insurance Backdrop” contemplates the government’s liability and response to a too-big-to-fail scenario or “catastrophic cyber incident.”

“We will explore how the government can stabilize insurance markets against catastrophic risk to drive better cybersecurity practices and to provide market certainty when catastrophic events do occur,” the strategy reads.

When the Bush administration released the first U.S. national cybersecurity strategy 20 years ago after the 9/11 attacks, the popular term for that same scenario was a “digital Pearl Harbor,” and there was a great deal of talk then about how the cyber insurance market would soon help companies shore up their cybersecurity practices.

In the wake of countless ransomware intrusions, many companies now hold cybersecurity insurance to help cover the considerable costs of responding to such intrusions. Leaving aside the question of whether insurance coverage has helped companies improve security, what happens if every one of these companies has to make a claim at the same time?

The notion of a Digital Pearl Harbor incident struck many experts at the time as a hyperbolic justification for expanding the government’s digital surveillance capabilities, and an overstatement of the capabilities of our adversaries. But back in 2003, most of the world’s companies didn’t host their entire business in the cloud.

Today, nobody questions the capabilities, goals and outcomes of dozens of nation-state level cyber adversaries. And these days, a catastrophic cyber incident could be little more than an extended, simultaneous outage at multiple cloud providers.

The full national cybersecurity strategy is available from the White House website (PDF).

Three different cybercriminal groups claimed access to internal networks at communications giant T-Mobile in more than 100 separate incidents throughout 2022, new data suggests. In each case, the goal of the attackers was the same: Phish T-Mobile employees for access to internal company tools, and then convert that access into a cybercrime service that could be hired to divert any T-Mobile user’s text messages and phone calls to another device.

The conclusions above are based on an extensive analysis of Telegram chat logs from three distinct cybercrime groups or actors that have been identified by security researchers as particularly active in and effective at “SIM-swapping,” which involves temporarily seizing control over a target’s mobile phone number.

Countless websites and online services use SMS text messages for both password resets and multi-factor authentication. This means that stealing someone’s phone number often can let cybercriminals hijack the target’s entire digital life in short order — including access to any financial, email and social media accounts tied to that phone number.

All three SIM-swapping entities that were tracked for this story remain active in 2023, and they all conduct business in open channels on the instant messaging platform Telegram. KrebsOnSecurity is not naming those channels or groups here because they will simply migrate to more private servers if exposed publicly, and for now those servers remain a useful source of intelligence about their activities.

Each advertises their claimed access to T-Mobile systems in a similar way. At a minimum, every SIM-swapping opportunity is announced with a brief “Tmobile up!” or “Tmo up!” message to channel participants. Other information in the announcements includes the price for a single SIM-swap request, and the handle of the person who takes the payment and information about the targeted subscriber.

The information required from the customer of the SIM-swapping service includes the target’s phone number, and the serial number tied to the new SIM card that will be used to receive text messages and phone calls from the hijacked phone number.

Initially, the goal of this project was to count how many times each entity claimed access to T-Mobile throughout 2022, by cataloging the various “Tmo up!” posts from each day and working backwards from Dec. 31, 2022.

But by the time we got to claims made in the middle of May 2022, completing the rest of the year’s timeline seemed unnecessary. The tally shows that in the last seven-and-a-half months of 2022, these groups collectively made SIM-swapping claims against T-Mobile on 104 separate days — often with multiple groups claiming access on the same days.

KrebsOnSecurity shared a large amount of data gathered for this story with T-Mobile. The company declined to confirm or deny any of these claimed intrusions. But in a written statement, T-Mobile said this type of activity affects the entire wireless industry.

“And we are constantly working to fight against it,” the statement reads. “We have continued to drive enhancements that further protect against unauthorized access, including enhancing multi-factor authentication controls, hardening environments, limiting access to data, apps or services, and more. We are also focused on gathering threat intelligence data, like what you have shared, to help further strengthen these ongoing efforts.”

TMO UP!

While it is true that each of these cybercriminal actors periodically offer SIM-swapping services for other mobile phone providers — including AT&T, Verizon and smaller carriers — those solicitations appear far less frequently in these group chats than T-Mobile swap offers. And when those offers do materialize, they are considerably more expensive.

The prices advertised for a SIM-swap against T-Mobile customers in the latter half of 2022 ranged between USD $1,000 and $1,500, while SIM-swaps offered against AT&T and Verizon customers often cost well more than twice that amount.

To be clear, KrebsOnSecurity is not aware of specific SIM-swapping incidents tied to any of these breach claims. However, the vast majority of advertisements for SIM-swapping claims against T-Mobile tracked in this story had two things in common that set them apart from random SIM-swapping ads on Telegram.

First, they included an offer to use a mutually trusted “middleman” or escrow provider for the transaction (to protect either party from getting scammed). More importantly, the cybercriminal handles that were posting ads for SIM-swapping opportunities from these groups generally did so on a daily or near-daily basis — often teasing their upcoming swap events in the hours before posting a “Tmo up!” message announcement.

In other words, if the crooks offering these SIM-swapping services were ripping off their customers or claiming to have access that they didn’t, this would be almost immediately obvious from the responses of the more seasoned and serious cybercriminals in the same chat channel.

There are plenty of people on Telegram claiming to have SIM-swap access at major telecommunications firms, but a great many such offers are simply four-figure scams, and any pretenders on this front are soon identified and banned (if not worse).

One of the groups that reliably posted “Tmo up!” messages to announce SIM-swap availability against T-Mobile customers also reliably posted “Tmo down!” follow-up messages announcing exactly when their claimed access to T-Mobile employee tools was discovered and revoked by the mobile giant.

A review of the timestamps associated with this group’s incessant “Tmo up” and “Tmo down” posts indicates that while their claimed access to employee tools usually lasted less than an hour, in some cases that access apparently went undiscovered for several hours or even days.

TMO TOOLS

How could these SIM-swapping groups be gaining access to T-Mobile’s network as frequently as they claim? Peppered throughout the daily chit-chat on their Telegram channels are solicitations for people urgently needed to serve as “callers,” or those who can be hired to social engineer employees over the phone into navigating to a phishing website and entering their employee credentials.

Allison Nixon is chief research officer for the New York City-based cybersecurity firm Unit 221B. Nixon said these SIM-swapping groups will typically call employees on their mobile devices, pretend to be someone from the company’s IT department, and then try to get the person on the other end of the line to visit a phishing website that mimics the company’s employee login page.

Nixon argues that many people in the security community tend to discount the threat from voice phishing attacks as somehow “low tech” and “low probability” threats.

“I see it as not low-tech at all, because there are a lot of moving parts to phishing these days,” Nixon said. “You have the caller who has the employee on the line, and the person operating the phish kit who needs to spin it up and down fast enough so that it doesn’t get flagged by security companies. Then they have to get the employee on that phishing site and steal their credentials.”

In addition, she said, often there will be yet another co-conspirator whose job it is to use the stolen credentials and log into employee tools. That person may also need to figure out how to make their device pass “posture checks,” a form of device authentication that some companies use to verify that each login is coming only from employee-issued phones or laptops.

For aspiring criminals with little experience in scam calling, there are plenty of sample call transcripts available on these Telegram chat channels that walk one through how to impersonate an IT technician at the targeted company — and how to respond to pushback or skepticism from the employee. Here’s a snippet from one such tutorial that appeared recently in one of the SIM-swapping channels:

“Hello this is James calling from Metro IT department, how’s your day today?”

(yea im doing good, how r u)

i’m doing great, thank you for asking

i’m calling in regards to a ticket we got last week from you guys, saying you guys were having issues with the network connectivity which also interfered with [Microsoft] Edge, not letting you sign in or disconnecting you randomly. We haven’t received any updates to this ticket ever since it was created so that’s why I’m calling in just to see if there’s still an issue or not….”

TMO DOWN!

The TMO UP data referenced above, combined with comments from the SIM-swappers themselves, indicate that while many of their claimed accesses to T-Mobile tools in the middle of 2022 lasted hours on end, both the frequency and duration of these events began to steadily decrease as the year wore on.

T-Mobile declined to discuss what it may have done to combat these apparent intrusions last year. However, one of the groups began to complain loudly in late October 2022 that T-Mobile must have been doing something that was causing their phished access to employee tools to die very soon after they obtained it.

One group even remarked that they suspected T-Mobile’s security team had begun monitoring their chats.

Indeed, the timestamps associated with one group’s TMO UP/TMO DOWN notices show that their claimed access was often limited to less than 15 minutes throughout November and December of 2022.

Whatever the reason, the calendar graphic above clearly shows that the frequency of claimed access to T-Mobile decreased significantly across all three SIM-swapping groups in the waning weeks of 2022.

SECURITY KEYS

T-Mobile US reported revenues of nearly $80 billion last year. It currently employs more than 71,000 people in the United States, any one of whom can be a target for these phishers.

T-Mobile declined to answer questions about what it may be doing to beef up employee authentication. But Nicholas Weaver, a researcher and lecturer at University of California, Berkeley’s International Computer Science Institute, said T-Mobile and all the major wireless providers should be requiring employees to use physical security keys for that second factor when logging into company resources.

“These breaches should not happen,” Weaver said. “Because T-Mobile should have long ago issued all employees security keys and switched to security keys for the second factor. And because security keys provably block this style of attack.”

The most commonly used security keys are inexpensive USB-based devices. A security key implements a form of multi-factor authentication known as Universal 2nd Factor (U2F), which allows the user to complete the login process simply by inserting the USB key and pressing a button on the device. The key works without the need for any special software drivers.

The allure of U2F devices for multi-factor authentication is that even if an employee who has enrolled a security key for authentication tries to log in at an impostor site, the company’s systems simply refuse to request the security key if the user isn’t on their employer’s legitimate website, and the login attempt fails. Thus, the second factor cannot be phished, either over the phone or Internet.

THE ROLE OF MINORS IN SIM-SWAPPING

Nixon said one confounding aspect of SIM-swapping is that these criminal groups tend to recruit teenagers to do their dirty work.

“A huge reason this problem has been allowed to spiral out of control is because children play such a prominent role in this form of breach,” Nixon said.

Nixon said SIM-swapping groups often advertise low-level jobs on places like Roblox and Minecraft, online games that are extremely popular with young adolescent males.

“Statistically speaking, that kind of recruiting is going to produce a lot of people who are underage,” she said. “They recruit children because they’re naive, you can get more out of them, and they have legal protections that other people over 18 don’t have.”

For example, she said, even when underage SIM-swappers are arrested, the offenders tend to go right back to committing the same crimes as soon as they’re released.

In January 2023, T-Mobile disclosed that a “bad actor” stole records on roughly 37 million current customers, including their name, billing address, email, phone number, date of birth, and T-Mobile account number.

In August 2021, T-Mobile acknowledged that hackers made off with the names, dates of birth, Social Security numbers and driver’s license/ID information on more than 40 million current, former or prospective customers who applied for credit with the company. That breach came to light after a hacker began selling the records on a cybercrime forum.

In the shadow of such mega-breaches, any damage from the continuous attacks by these SIM-swapping groups can seem insignificant by comparison. But Nixon says it’s a mistake to dismiss SIM-swapping as a low volume problem.

“Logistically, you may only be able to get a few dozen or a hundred SIM-swaps in a day, but you can pick any customer you want across their entire customer base,” she said. “Just because a targeted account takeover is low volume doesn’t mean it’s low risk. These guys have crews that go and identify people who are high net worth individuals and who have a lot to lose.”

Nixon said another aspect of SIM-swapping that causes cybersecurity defenders to dismiss the threat from these groups is the perception that they are full of low-skilled “script kiddies,” a derisive term used to describe novice hackers who rely mainly on point-and-click hacking tools.

“They underestimate these actors and say this person isn’t technically sophisticated,” she said. “But if you’re rolling around in millions worth of stolen crypto currency, you can buy that sophistication. I know for a fact some of these compromises were at the hands of these ‘script kiddies,’ but they’re not ripping off other people’s scripts so much as hiring people to make scripts for them. And they don’t care what gets the job done, as long as they get to steal the money.”

Web hosting giant GoDaddy made headlines this month when it disclosed that a multi-year breach allowed intruders to steal company source code, siphon customer and employee login credentials, and foist malware on customer websites. Media coverage understandably focused on GoDaddy’s admission that it suffered three different cyberattacks over as many years at the hands of the same hacking group.  But it’s worth revisiting how this group typically got in to targeted companies: By calling employees and tricking them into navigating to a phishing website.

In a filing with the U.S. Securities and Exchange Commission (SEC), GoDaddy said it determined that the same “sophisticated threat actor group” was responsible for three separate intrusions, including:

-March 2020: A spear-phishing attack on a GoDaddy employee compromised the hosting login credentials of approximately 28,000 GoDaddy customers, as well as login credentials for a small number employees;

-November 2021: A compromised GoDaddy password let attackers steal source code and information tied to 1.2 million customers, including website administrator passwords, sFTP credentials, and private SSL keys;

-December 2022: Hackers gained access to and installed malware on GoDaddy’s cPanel hosting servers that “intermittently redirected random customer websites to malicious sites.”

“Based on our investigation, we believe these incidents are part of a multi-year campaign by a sophisticated threat actor group that, among other things, installed malware on our systems and obtained pieces of code related to some services within GoDaddy,” the company stated in its SEC filing.

What else do we know about the cause of these incidents? We don’t know much about the source of the November 2021 incident, other than GoDaddy’s statement that it involved a compromised password, and that it took about two months for the company to detect the intrusion. GoDaddy has not disclosed the source of the breach in December 2022 that led to malware on some customer websites.

But we do know the March 2020 attack was precipitated by a spear-phishing attack against a GoDaddy employee. GoDaddy described the incident at the time in general terms as a social engineering attack, but one of its customers affected by that March 2020 breach actually spoke to one of the hackers involved.

The hackers were able to change the Domain Name System (DNS) records for the transaction brokering site escrow.com so that it pointed to an address in Malaysia that was host to just a few other domains, including the then brand-new phishing domain servicenow-godaddy[.]com.

The general manager of Escrow.com found himself on the phone with one of the GoDaddy hackers, after someone who claimed they worked at GoDaddy called and said they needed him to authorize some changes to the account.

In reality, the caller had just tricked a GoDaddy employee into giving away their credentials, and he could see from the employee’s account that Escrow.com required a specific security procedure to complete a domain transfer.

The general manager of Escrow.com said he suspected the call was a scam, but decided to play along for about an hour — all the while recording the call and coaxing information out of the scammer.

“This guy had access to the notes, and knew the number to call,” to make changes to the account, the CEO of Escrow.com told KrebsOnSecurity. “He was literally reading off the tickets to the notes of the admin panel inside GoDaddy.”

About halfway through this conversation — after being called out by the general manager as an imposter — the hacker admitted that he was not a GoDaddy employee, and that he was in fact part of a group that enjoyed repeated success with social engineering employees at targeted companies over the phone.

Absent from GoDaddy’s SEC statement is another spate of attacks in November 2020, in which unknown intruders redirected email and web traffic for multiple cryptocurrency services that used GoDaddy in some capacity.

It is possible this incident was not mentioned because it was the work of yet another group of intruders. But in response to questions from KrebsOnSecurity at the time, GoDaddy said that incident also stemmed from a “limited” number of GoDaddy employees falling for a sophisticated social engineering scam.

“As threat actors become increasingly sophisticated and aggressive in their attacks, we are constantly educating employees about new tactics that might be used against them and adopting new security measures to prevent future attacks,” GoDaddy said in a written statement back in 2020.

Voice phishing or “vishing” attacks typically target employees who work remotely. The phishers will usually claim that they’re calling from the employer’s IT department, supposedly to help troubleshoot some issue. The goal is to convince the target to enter their credentials at a website set up by the attackers that mimics the organization’s corporate email or VPN portal.

Experts interviewed for an August 2020 story on a steep rise in successful voice phishing attacks said there are generally at least two people involved in each vishing scam: One who is social engineering the target over the phone, and another co-conspirator who takes any credentials entered at the phishing page — including multi-factor authentication codes shared by the victim — and quickly uses them to log in to the company’s website.

The attackers are usually careful to do nothing with the phishing domain until they are ready to initiate a vishing call to a potential victim. And when the attack or call is complete, they disable the website tied to the domain.

This is key because many domain registrars will only respond to external requests to take down a phishing website if the site is live at the time of the abuse complaint. This tactic also can stymie efforts by companies that focus on identifying newly-registered phishing domains before they can be used for fraud.

GoDaddy’s latest SEC filing indicates the company had nearly 7,000 employees as of December 2022. In addition, GoDaddy contracts with another 3,000 people who work full-time for the company via business process outsourcing companies based primarily in India, the Philippines and Colombia.

Many companies now require employees to supply a one-time password — such as one sent via SMS or produced by a mobile authenticator app — in addition to their username and password when logging in to company assets online. But both SMS and app-based codes can be undermined by phishing attacks that simply request this information in addition to the user’s password.

One multifactor option — physical security keys — appears to be immune to these advanced scams. The most commonly used security keys are inexpensive USB-based devices. A security key implements a form of multi-factor authentication known as Universal 2nd Factor (U2F), which allows the user to complete the login process simply by inserting the USB device and pressing a button on the device. The key works without the need for any special software drivers.

The allure of U2F devices for multi-factor authentication is that even if an employee who has enrolled a security key for authentication tries to log in at an impostor site, the company’s systems simply refuse to request the security key if the user isn’t on their employer’s legitimate website, and the login attempt fails. Thus, the second factor cannot be phished, either over the phone or Internet.

In July 2018, Google disclosed that it had not had any of its 85,000+ employees successfully phished on their work-related accounts since early 2017, when it began requiring all employees to use physical security keys in place of one-time codes.