vishing

GoDaddy Employees Used in Attacks on Multiple Cryptocurrency Services

Fraudsters redirected email and web traffic destined for several cryptocurrency trading platforms over the past week. The attacks were facilitated by scams targeting employees at GoDaddy, the world’s largest domain name registrar, KrebsOnSecurity has learned.

The incident is the latest incursion at GoDaddy that relied on tricking employees into transferring ownership and/or control over targeted domains to fraudsters. In March, a voice phishing scam targeting GoDaddy support employees allowed attackers to assume control over at least a half-dozen domain names, including transaction brokering site escrow.com.

And in May of this year, GoDaddy disclosed that 28,000 of its customers’ web hosting accounts were compromised following a security incident in Oct. 2019 that wasn’t discovered until April 2020.

This latest campaign appears to have begun on or around Nov. 13, with an attack on cryptocurrency trading platform liquid.com.

“A domain hosting provider ‘GoDaddy’ that manages one of our core domain names incorrectly transferred control of the account and domain to a malicious actor,” Liquid CEO Mike Kayamori said in a blog post. “This gave the actor the ability to change DNS records and in turn, take control of a number of internal email accounts. In due course, the malicious actor was able to partially compromise our infrastructure, and gain access to document storage.”

In the early morning hours of Nov. 18 Central European Time (CET), cyptocurrency mining service NiceHash disccovered that some of the settings for its domain registration records at GoDaddy were changed without authorization, briefly redirecting email and web traffic for the site. NiceHash froze all customer funds for roughly 24 hours until it was able to verify that its domain settings had been changed back to their original settings.

“At this moment in time, it looks like no emails, passwords, or any personal data were accessed, but we do suggest resetting your password and activate 2FA security,” the company wrote in a blog post.

NiceHash founder Matjaz Skorjanc said the unauthorized changes were made from an Internet address at GoDaddy, and that the attackers tried to use their access to its incoming NiceHash emails to perform password resets on various third-party services, including Slack and Github. But he said GoDaddy was impossible to reach at the time because it was undergoing a widespread system outage in which phone and email systems were unresponsive.

“We detected this almost immediately [and] started to mitigate [the] attack,” Skorjanc said in an email to this author. “Luckily, we fought them off well and they did not gain access to any important service. Nothing was stolen.”

Skorjanc said NiceHash’s email service was redirected to privateemail.com, an email platform run by Namecheap Inc., another large domain name registrar. Using Farsight Security, a service which maps changes to domain name records over time, KrebsOnSecurity instructed the service to show all domains registered at GoDaddy that had alterations to their email records in the past week which pointed them to privateemail.com. Those results were then indexed against the top one million most popular websites according to Alexa.com.

The result shows that several other cryptocurrency platforms also may have been targeted by the same group, including Bibox.com, Celsius.network, and Wirex.app. None of these companies responded to requests for comment.

In response to questions from KrebsOnSecurity, GoDaddy acknowledged that “a small number” of customer domain names had been modified after a “limited” number of GoDaddy employees fell for a social engineering scam. GoDaddy said the outage between 7:00 p.m. and 11:00 p.m. PST on Nov. 17 was not related to a security incident, but rather a technical issue that materialized during planned network maintenance.

“Separately, and unrelated to the outage, a routine audit of account activity identified potential unauthorized changes to a small number of customer domains and/or account information,” GoDaddy spokesperson Dan Race said. “Our security team investigated and confirmed threat actor activity, including social engineering of a limited number of GoDaddy employees.

“We immediately locked down the accounts involved in this incident, reverted any changes that took place to accounts, and assisted affected customers with regaining access to their accounts,” GoDaddy’s statement continued. “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.”

Race declined to specify how its employees were tricked into making the unauthorized changes, saying the matter was still under investigation. But in the attacks earlier this year that affected escrow.com and several other GoDaddy customer domains, the assailants targeted employees over the phone, and were able to read internal notes that GoDaddy employees had left on customer accounts.

What’s more, the attack on escrow.com redirected the site to an Internet address in Malaysia that hosted fewer than a dozen other domains, including the phishing website servicenow-godaddy.com. This suggests the attackers behind the March incident — and possibly this latest one — succeeded by calling GoDaddy employees and convincing them to use their employee credentials at a fraudulent GoDaddy login page.

In August 2020, KrebsOnSecurity warned about a marked increase in large corporations being targeted in sophisticated voice phishing or “vishing” scams. Experts say the success of these scams has been aided greatly by many employees working remotely thanks to the ongoing Coronavirus pandemic.

A typical vishing scam begins with a series of phone calls to employees working remotely at a targeted organization. The phishers often will explain that they’re calling from the employer’s IT department to help troubleshoot issues with the company’s email or virtual private networking (VPN) technology.

The goal is to convince the target either to divulge their credentials over the phone or to input them manually at a website set up by the attackers that mimics the organization’s corporate email or VPN portal.

On July 15, a number of high-profile Twitter accounts were used to tweet out a bitcoin scam that earned more than $100,000 in a few hours. According to Twitter, that attack succeeded because the perpetrators were able to social engineer several Twitter employees over the phone into giving away access to internal Twitter tools.

An alert issued jointly by the FBI and the Cybersecurity and Infrastructure Security Agency (CISA) says the perpetrators of these vishing attacks compile dossiers on employees at their targeted companies using mass scraping of public profiles on social media platforms, recruiter and marketing tools, publicly available background check services, and open-source research.

The FBI/CISA advisory includes a number of suggestions that companies can implement to help mitigate the threat from vishing attacks, including:

• Restrict VPN connections to managed devices only, using mechanisms like hardware checks or installed certificates, so user input alone is not enough to access the corporate VPN.

• Restrict VPN access hours, where applicable, to mitigate access outside of allowed times.

• Employ domain monitoring to track the creation of, or changes to, corporate, brand-name domains.

• Actively scan and monitor web applications for unauthorized access, modification, and anomalous activities.

• Employ the principle of least privilege and implement software restriction policies or other controls; monitor authorized user accesses and usage.

• Consider using a formalized authentication process for employee-to-employee communications made over the public telephone network where a second factor is used to
authenticate the phone call before sensitive information can be discussed.

• Improve 2FA and OTP messaging to reduce confusion about employee authentication attempts.

• Verify web links do not have misspellings or contain the wrong domain.

• Bookmark the correct corporate VPN URL and do not visit alternative URLs on the sole basis of an inbound phone call.

• Be suspicious of unsolicited phone calls, visits, or email messages from unknown individuals claiming to be from a legitimate organization. Do not provide personal information or information about your organization, including its structure or networks, unless you are certain of a person’s authority to have the information. If possible, try to verify the caller’s identity directly with the company.

• If you receive a vishing call, document the phone number of the caller as well as the domain that the actor tried to send you to and relay this information to law enforcement.

• Limit the amount of personal information you post on social networking sites. The internet is a public resource; only post information you are comfortable with anyone seeing.

• Evaluate your settings: sites may change their options periodically, so review your security and privacy settings regularly to make sure that your choices are still appropriate.

Two Charged in SIM Swapping, Vishing Scams

Two young men from the eastern United States have been hit with identity theft and conspiracy charges for allegedly stealing bitcoin and social media accounts by tricking employees at wireless phone companies into giving away credentials needed to remotely access and modify customer account information.

Prosecutors say Jordan K. Milleson, 21 of Timonium, Md. and 19-year-old Kingston, Pa. resident Kyell A. Bryan hijacked social media and bitcoin accounts using a mix of voice phishing or “vishing” attacks and “SIM swapping,” a form of fraud that involves bribing or tricking employees at mobile phone companies.

Investigators allege the duo set up phishing websites that mimicked legitimate employee portals belonging to wireless providers, and then emailed and/or called employees at these providers in a bid to trick them into logging in at these fake portals.

According to the indictment (PDF), Milleson and Bryan used their phished access to wireless company employee tools to reassign the subscriber identity module (SIM) tied to a target’s mobile device. A SIM card is a small, removable smart chip in mobile phones that links the device to the customer’s phone number, and their purloined access to employee tools meant they could reassign any customer’s phone number to a SIM card in a mobile device they controlled.

That allowed them to seize control over a target’s incoming phone calls and text messages, which were used to reset the password for email, social media and cryptocurrency accounts tied to those numbers.

Interestingly, the conspiracy appears to have unraveled over a business dispute between the two men. Prosecutors say on June 26, 2019, “Bryan called the Baltimore County Police Department and falsely reported that he, purporting to be a resident of the Milleson family residence, had shot his father at the residence.”

“During the call, Bryan, posing as the purported shooter, threatened to shoot himself and to shoot at police officers if they attempted to confront him,” reads a statement from the U.S. Attorney’s Office for the District of Maryland. “The call was a ‘swatting’ attack, a criminal harassment tactic in which a person places a false call to authorities that will trigger a police or special weapons and tactics (SWAT) team response — thereby causing a life-threatening situation.”

The indictment alleges Bryan swatted his alleged partner in retaliation for Milleson failing to share the proceeds of a digital currency theft. Milleson and Bryan are facing charges of wire fraud, unauthorized access to protected computers, aggravated identity theft and wire fraud conspiracy.

The indictment doesn’t specify the wireless companies targeted by the phishing and vishing schemes, but sources close to the investigation tell KrebsOnSecurity the two men were active members of OGusers, an online forum that caters to people selling access to hijacked social media accounts.

Bryan allegedly used the nickname “Champagne” on OGusers. On at least two occasions in the past few years, the OGusers forum was hacked and its user database — including private messages between forum members — were posted online. In a private message dated Nov. 15, 2019, Champagne can be seen asking another OGusers member to create a phishing site mimicking T-Mobile’s employee login page (t-mobileupdates[.]com).

Sources tell KrebsOnSecurity the two men are part of a larger conspiracy involving individuals from the United States and United Kingdom who’ve used vishing and phishing to trick work-at-home employees into giving away credentials needed to remotely access their employers’ networks.

FBI, CISA Echo Warnings on ‘Vishing’ Threat

The Federal Bureau of Investigation (FBI) and the Cybersecurity and Infrastructure Security Agency (CISA) on Thursday issued a joint alert to warn about the growing threat from voice phishing or “vishing” attacks targeting companies. The advisory came less than 24 hours after KrebsOnSecurity published an in-depth look at a crime group offering a service that people can hire to steal VPN credentials and other sensitive data from employees working remotely during the Coronavirus pandemic.

“The COVID-19 pandemic has resulted in a mass shift to working from home, resulting in increased use of corporate virtual private networks (VPNs) and elimination of in-person verification,” the alert reads. “In mid-July 2020, cybercriminals started a vishing campaign—gaining access to employee tools at multiple companies with indiscriminate targeting — with the end goal of monetizing the access.”

As noted in Wednesday’s story, the agencies said the phishing sites set up by the attackers tend to include hyphens, the target company’s name, and certain words — such as “support,” “ticket,” and “employee.” The perpetrators focus on social engineering new hires at the targeted company, and impersonate staff at the target company’s IT helpdesk.

The joint FBI/CISA alert (PDF) says the vishing gang also compiles dossiers on employees at the specific companies using mass scraping of public profiles on social media platforms, recruiter and marketing tools, publicly available background check services, and open-source research. From the alert:

“Actors first began using unattributed Voice over Internet Protocol (VoIP) numbers to call targeted employees on their personal cellphones, and later began incorporating spoofed numbers of other offices and employees in the victim company. The actors used social engineering techniques and, in some cases, posed as members of the victim company’s IT help desk, using their knowledge of the employee’s personally identifiable information—including name, position, duration at company, and home address—to gain the trust of the targeted employee.”

“The actors then convinced the targeted employee that a new VPN link would be sent and required their login, including any 2FA [2-factor authentication] or OTP [one-time passwords]. The actor logged the information provided by the employee and used it in real-time to gain access to corporate tools using the employee’s account.”

The alert notes that in some cases the unsuspecting employees approved the 2FA or OTP prompt, either accidentally or believing it was the result of the earlier access granted to the help desk impersonator. In other cases, the attackers were able to intercept the one-time codes by targeting the employee with SIM swapping, which involves social engineering people at mobile phone companies into giving them control of the target’s phone number.

The agencies said crooks use the vished VPN credentials to mine the victim company databases for their customers’ personal information to leverage in other attacks.

“The actors then used the employee access to conduct further research on victims, and/or to fraudulently obtain funds using varying methods dependent on the platform being accessed,” the alert reads. “The monetizing method varied depending on the company but was highly aggressive with a tight timeline between the initial breach and the disruptive cashout scheme.”

The advisory includes a number of suggestions that companies can implement to help mitigate the threat from these vishing attacks, including:

• Restrict VPN connections to managed devices only, using mechanisms like hardware checks or installed certificates, so user input alone is not enough to access the corporate VPN.

• Restrict VPN access hours, where applicable, to mitigate access outside of allowed times.

• Employ domain monitoring to track the creation of, or changes to, corporate, brand-name domains.

• Actively scan and monitor web applications for unauthorized access, modification, and anomalous activities.

• Employ the principle of least privilege and implement software restriction policies or other controls; monitor authorized user accesses and usage.

• Consider using a formalized authentication process for employee-to-employee communications made over the public telephone network where a second factor is used to
authenticate the phone call before sensitive information can be discussed.

• Improve 2FA and OTP messaging to reduce confusion about employee authentication attempts.

• Verify web links do not have misspellings or contain the wrong domain.

• Bookmark the correct corporate VPN URL and do not visit alternative URLs on the sole basis of an inbound phone call.

• Be suspicious of unsolicited phone calls, visits, or email messages from unknown individuals claiming to be from a legitimate organization. Do not provide personal information or information about your organization, including its structure or networks, unless you are certain of a person’s authority to have the information. If possible, try to verify the caller’s identity directly with the company.

• If you receive a vishing call, document the phone number of the caller as well as the domain that the actor tried to send you to and relay this information to law enforcement.

• Limit the amount of personal information you post on social networking sites. The internet is a public resource; only post information you are comfortable with anyone seeing.

• Evaluate your settings: sites may change their options periodically, so review your security and privacy settings regularly to make sure that your choices are still appropriate.

Voice Phishers Targeting Corporate VPNs

The COVID-19 epidemic has brought a wave of email phishing attacks that try to trick work-at-home employees into giving away credentials needed to remotely access their employers’ networks. But one increasingly brazen group of crooks is taking your standard phishing attack to the next level, marketing a voice phishing service that uses a combination of one-on-one phone calls and custom phishing sites to steal VPN credentials from employees.

According to interviews with several sources, this hybrid phishing gang has a remarkably high success rate, and operates primarily through paid requests or “bounties,” where customers seeking access to specific companies or accounts can hire them to target employees working remotely at home.

And over the past six months, the criminals responsible have created dozens if not hundreds of phishing pages targeting some of the world’s biggest corporations. For now at least, they appear to be focusing primarily on companies in the financial, telecommunications and social media industries.

“For a number of reasons, this kind of attack is really effective,” said Allison Nixon, chief research officer at New York-based cyber investigations firm Unit 221B. “Because of the Coronavirus, we have all these major corporations that previously had entire warehouses full of people who are now working remotely. As a result the attack surface has just exploded.”

TARGET: NEW HIRES

A typical engagement begins with a series of phone calls to employees working remotely at a targeted organization. The phishers will explain that they’re calling from the employer’s IT department to help troubleshoot issues with the company’s virtual private networking (VPN) technology.

The employee phishing page bofaticket[.]com. Image: urlscan.io

The goal is to convince the target either to divulge their credentials over the phone or to input them manually at a website set up by the attackers that mimics the organization’s corporate email or VPN portal.

Zack Allen is director of threat intelligence for ZeroFOX, a Baltimore-based company that helps customers detect and respond to risks found on social media and other digital channels. Allen has been working with Nixon and several dozen other researchers from various security firms to monitor the activities of this prolific phishing gang in a bid to disrupt their operations.

Allen said the attackers tend to focus on phishing new hires at targeted companies, and will often pose as new employees themselves working in the company’s IT division. To make that claim more believable, the phishers will create LinkedIn profiles and seek to connect those profiles with other employees from that same organization to support the illusion that the phony profile actually belongs to someone inside the targeted firm.

“They’ll say ‘Hey, I’m new to the company, but you can check me out on LinkedIn’ or Microsoft Teams or Slack, or whatever platform the company uses for internal communications,” Allen said. “There tends to be a lot of pretext in these conversations around the communications and work-from-home applications that companies are using. But eventually, they tell the employee they have to fix their VPN and can they please log into this website.”

SPEAR VISHING

The domains used for these pages often invoke the company’s name, followed or preceded by hyphenated terms such as “vpn,” “ticket,” “employee,” or “portal.” The phishing sites also may include working links to the organization’s other internal online resources to make the scheme seem more believable if a target starts hovering over links on the page.

Allen said a typical voice phishing or “vishing” attack by this group involves at least two perpetrators: One who is social engineering the target over the phone, and another co-conspirator who takes any credentials entered at the phishing page and quickly uses them to log in to the target company’s VPN platform in real-time.

Time is of the essence in these attacks because many companies that rely on VPNs for remote employee access also require employees to supply some type of multi-factor authentication in addition to a username and password — such as a one-time numeric code generated by a mobile app or text message. And in many cases, those codes are only good for a short duration — often measured in seconds or minutes.

But these vishers can easily sidestep that layer of protection, because their phishing pages simply request the one-time code as well.

A phishing page (helpdesk-att[.]com) targeting AT&T employees. Image: urlscan.io

Allen said it matters little to the attackers if the first few social engineering attempts fail. Most targeted employees are working from home or can be reached on a mobile device. If at first the attackers don’t succeed, they simply try again with a different employee.

And with each passing attempt, the phishers can glean important details from employees about the target’s operations, such as company-specific lingo used to describe its various online assets, or its corporate hierarchy.

Thus, each unsuccessful attempt actually teaches the fraudsters how to refine their social engineering approach with the next mark within the targeted organization, Nixon said.

“These guys are calling companies over and over, trying to learn how the corporation works from the inside,” she said.

NOW YOU SEE IT, NOW YOU DON’T

All of the security researchers interviewed for this story said the phishing gang is pseudonymously registering their domains at just a handful of domain registrars that accept bitcoin, and that the crooks typically create just one domain per registrar account.

“They’ll do this because that way if one domain gets burned or taken down, they won’t lose the rest of their domains,” Allen said.

More importantly, the attackers are 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 requirement can stymie efforts by companies like ZeroFOX that focus on identifying newly-registered phishing domains before they can be used for fraud.

“They’ll only boot up the website and have it respond at the time of the attack,” Allen said. “And it’s super frustrating because if you file an abuse ticket with the registrar and say, ‘Please take this domain away because we’re 100 percent confident this site is going to be used for badness,’ they won’t do that if they don’t see an active attack going on. They’ll respond that according to their policies, the domain has to be a live phishing site for them to take it down. And these bad actors know that, and they’re exploiting that policy very effectively.”

A phishing page (github-ticket[.]com) aimed at siphoning credentials for a target organization’s access to the software development platform Github. Image: urlscan.io

SCHOOL OF HACKS

Both Nixon and Allen said the object of these phishing attacks seems to be to gain access to as many internal company tools as possible, and to use those tools to seize control over digital assets that can quickly be turned into cash. Primarily, that includes any social media and email accounts, as well as associated financial instruments such as bank accounts and any cryptocurrencies.

Nixon said she and others in her research group believe the people behind these sophisticated vishing campaigns hail from a community of young men who have spent years learning how to social engineer employees at mobile phone companies and social media firms into giving up access to internal company tools.

Traditionally, the goal of these attacks has been gaining control over highly-prized social media accounts, which can sometimes fetch thousands of dollars when resold in the cybercrime underground. But this activity gradually has evolved toward more direct and aggressive monetization of such access.

On July 15, a number of high-profile Twitter accounts were used to tweet out a bitcoin scam that earned more than $100,000 in a few hours. According to Twitter, that attack succeeded because the perpetrators were able to social engineer several Twitter employees over the phone into giving away access to internal Twitter tools.

Nixon said it’s not clear whether any of the people involved in the Twitter compromise are associated with this vishing gang, but she noted that the group showed no signs of slacking off after federal authorities charged several people with taking part in the Twitter hack.

“A lot of people just shut their brains off when they hear the latest big hack wasn’t done by hackers in North Korea or Russia but instead some teenagers in the United States,” Nixon said. “When people hear it’s just teenagers involved, they tend to discount it. But the kinds of people responsible for these voice phishing attacks have now been doing this for several years. And unfortunately, they’ve gotten pretty advanced, and their operational security is much better now.”

A phishing page (vzw-employee[.]com) targeting employees of Verizon. Image: DomainTools

PROPER ADULT MONEY-LAUNDERING

While it may seem amateurish or myopic for attackers who gain access to a Fortune 100 company’s internal systems to focus mainly on stealing bitcoin and social media accounts, that access — once established — can be re-used and re-sold to others in a variety of ways.

“These guys do intrusion work for hire, and will accept money for any purpose,” Nixon said. “This stuff can very quickly branch out to other purposes for hacking.”

For example, Allen said he suspects that once inside of a target company’s VPN, the attackers may try to add a new mobile device or phone number to the phished employee’s account as a way to generate additional one-time codes for future access by the phishers themselves or anyone else willing to pay for that access.

Nixon and Allen said the activities of this vishing gang have drawn the attention of U.S. federal authorities, who are growing concerned over indications that those responsible are starting to expand their operations to include criminal organizations overseas.

“What we see now is this group is really good on the intrusion part, and really weak on the cashout part,” Nixon said. “But they are learning how to maximize the gains from their activities. That’s going to require interactions with foreign gangs and learning how to do proper adult money laundering, and we’re already seeing signs that they’re growing up very quickly now.”

WHAT CAN COMPANIES DO?

Many companies now make security awareness and training an integral part of their operations. Some firms even periodically send test phishing messages to their employees to gauge their awareness levels, and then require employees who miss the mark to undergo additional training.

Such precautions, while important and potentially helpful, may do little to combat these phone-based phishing attacks that tend to target new employees. Both Allen and Nixon — as well as others interviewed for this story who asked not to be named — said the weakest link in most corporate VPN security setups these days is the method relied upon for multi-factor authentication.

A U2F device made by Yubikey, plugged into the USB port on a computer.

One multi-factor option — physical security keys — appears to be immune to these sophisticated 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.

Probably the most popular maker of security keys is Yubico, which sells a basic U2F Yubikey for $20. It offers regular USB versions as well as those made for devices that require USB-C connections, such as Apple’s newer Mac OS systems. Yubico also sells more expensive keys designed to work with mobile devices. [Full disclosure: Yubico was recently an advertiser on this site].

Nixon said many companies will likely balk at the price tag associated with equipping each employee with a physical security key. But she said as long as most employees continue to work remotely, this is probably a wise investment given the scale and aggressiveness of these voice phishing campaigns.

“The truth is some companies are in a lot of pain right now, and they’re having to put out fires while attackers are setting new fires,” she said. “Fixing this problem is not going to be simple, easy or cheap. And there are risks involved if you somehow screw up a bunch of employees accessing the VPN. But apparently these threat actors really hate Yubikey right now.”