One of the oldest scams around — the fake job interview that seeks only to harvest your personal and financial data — is on the rise, the FBI warns. Here’s the story of a recent LinkedIn impersonation scam that led to more than 100 people getting duped, and one almost-victim who decided the job offer was too-good-to-be-true.

Last week, someone began began posting classified notices on LinkedIn for different design consulting jobs at Geosyntec Consultants, an environmental engineering firm based in the Washington, D.C. area. Those who responded were told their application for employment was being reviewed and that they should email Troy Gwin — Geosyntec’s senior recruiter — immediately to arrange a screening interview.

Gwin contacted KrebsOnSecurity after hearing from job seekers trying to verify the ad, which urged respondents to email Gwin at a Gmail address that was not his. Gwin said LinkedIn told him roughly 100 people applied before the phony ads were removed for abusing the company’s terms of service.

“The endgame was to offer a job based on successful completion of background check which obviously requires entering personal information,” Gwin said. “Almost 100 people applied. I feel horrible about this. These people were really excited about this ‘opportunity’.”

Erica Siegel was particularly excited about the possibility of working in a creative director role she interviewed for at the fake Geosyntec. Siegel said her specialty — helping wealthy people develop their own personal brands — has been in low demand throughout the pandemic, so she’s applied to dozens of jobs and freelance gigs over the past few months.

On Monday, someone claiming to work with Gwin contacted Siegel and asked her to set up an online interview with Geosyntec. Siegel said the “recruiter” sent her a list of screening questions that all seemed relevant to the position being advertised.

Siegel said that within about an hour of submitting her answers, she received a reply saying the company’s board had unanimously approved her as a new hire, with an incredibly generous salary considering she had to do next to no work to get a job she could do from home.

Worried that her potential new dream job might be too-good-to-be-true, she sent the recruiter a list of her own questions that she had about the role and its position within the company.

But the recruiter completely ignored Siegel’s follow-up questions, instead sending a reply that urged her to get in touch with a contact in human resources to immediately begin the process of formalizing her employment. Which of course involves handing over one’s personal (driver’s license info) and financial details for direct deposit.

Multiple things about this job offer didn’t smell right to Siegel.

“I usually have six or seven interviews before getting a job,” Siegel said. “Hardly ever in my lifetime have I seen a role that flexible, completely remote and paid the kind of money I would ask for. You never get all three of those things.”

So she called her dad, an environmental attorney who happens to know and have worked with people at the real Geosyntec Consultants. Then she got in touch with the real Troy Gwin, who confirmed her suspicions that the whole thing was a scam.

“Even after the real Troy said they’d gotten these [LinkedIn] ads shut down, this guy was still emailing me asking for my HR information,” Siegel said. “So my dad said, ‘Troll him back, and tell him you want a signing bonus via money order.’ I was like, okay, what’s the worst that could happen? I never heard from him again.”

HOW TO SPOT A JOB SCAM

In late April, the FBI warned that technology is making these scams easier and more lucrative for fraudsters, who are particularly fond of impersonating recruiters.

“Fake Job or Employment Scams occur when criminal actors deceive victims into believing they have a job or a potential job,” the FBI warned. “Criminals leverage their position as “employers” to persuade victims to provide them with personally identifiable information (PII), become unwitting money mules, or to send them money.”

Last year, some 16,012 people reported being victims of employment scams with losses totaling more than $59 million, according to the FBI’s Internet Crime Complaint Center (IC3). But the real losses each year from employment scams are likely far higher; as the Justice Department often points out, relatively few victims of these crimes report the matter to the IC3.

LinkedIn said its platform uses automated and manual defenses to detect and address fake accounts or fraudulent payments.

“Any accounts or job posts that violate our policies are blocked from the site,” LinkedIn said in response to a request for comment. “The majority of fake job postings are stopped before going live on our site, and for those job postings that aren’t, whenever we find fake posts, we work to remove it quickly.”

LinkedIn’s most recent transparency report says these automated defenses block or automatically remove 98.4% of the fake accounts. But the scam that ensnared Gwin and Siegel is more of a hybrid, in that the majority of it operates outside of LinkedIn’s control via email services like Gmail and Yahoo.

This, by the way, should be a major red flag for anyone searching for a job, says the FBI: “Potential employers contact victims through non-company email domains and teleconference applications.”

Here are some other telltale signs of a job scam, as per the FBI:

-Interviews are not conducted in-person or through a secure video call.
-Potential employers contact victims through non-company email domains and teleconference applications.
-Potential employers require employees to purchase start-up equipment from the company.
-Potential employers require employees to pay upfront for background investigations or screenings.
-Potential employers request credit card information.
-Potential employers send an employment contract to physically sign asking for PII.
-Job postings appear on job boards, but not on the companies’ websites.
-Recruiters or managers do not have profiles on the job board, or the profiles do not seem to fit their roles.

Many online services allow users to reset their passwords by clicking a link sent via SMS, and this unfortunately widespread practice has turned mobile phone numbers into de facto identity documents. Which means losing control over one thanks to a divorce, job termination or financial crisis can be devastating.

Even so, plenty of people willingly abandon a mobile number without considering the potential fallout to their digital identities when those digits invariably get reassigned to someone else. New research shows how fraudsters can abuse wireless provider websites to identify available, recycled mobile numbers that allow password resets at a range of email providers and financial services online.

Researchers in the computer science department at Princeton University say they sampled 259 phone numbers at two major wireless carriers, and found 171 of them were tied to existing accounts at popular websites, potentially allowing those accounts to be hijacked.

The Princeton team further found 100 of those 259 numbers were linked to leaked login credentials on the web, which could enable account hijackings that defeat SMS-based multi-factor authentication.

“Our key finding is that attackers can feasibly leverage number recycling to target previous owners and their accounts,” the researchers wrote. “The moderate to high hit rates of our testing methods indicate that most recycled numbers are vulnerable to these attacks. Furthermore, by focusing on blocks of Likely recycled numbers, an attacker can easily discover available recycled numbers, each of which then becomes a potential target.”

The researchers located newly-recycled mobile numbers by browsing numbers made available to customers interested in signing up for a prepaid account at T-Mobile or Verizon (apparently AT&T doesn’t provide a similar interface). They said they were able to identify and ignore large blocks of new, unused numbers, as these blocks tend to be made available consecutively — much like newly printed money is consecutively numbered in stacks.

The Princeton team has a number of recommendations for T-Mobile and Verizon, noting that both carriers allow unlimited inquiries on their prepaid customer platforms online — meaning there is nothing to stop attackers from automating this type of number reconnaissance.

“On postpaid interfaces, Verizon already has safeguards and T-Mobile does not even support changing numbers online,” the researchers wrote. “However, the number pool is shared between postpaid and prepaid, rendering all subscribers vulnerable to attacks.”

They also recommend the carriers teach their support employees to remind customers about the risks of relinquishing a mobile number without first disconnecting it from other identities and sites online, advice they generally did not find was offered when interacting with customer support regarding number changes.

In addition, the carriers could offer their own “number parking” service for customers who know they will not require phone service for an extended period of time, or for those who just aren’t sure what they want to do with a number. Such services are already offered by companies like NumberBarn and Park My Phone, and they generally cost between $2-5 per month.

The Princeton study recommends consumers who are considering a number change instead either store the digits at an existing number parking service, or “port” the number to something like Google Voice. For a one-time $20 fee, Google Voice will let you port the number, and then you can continue to receive texts and calls to that number via Google Voice, or you can forward them to another number.

Porting seems like less of a hassle and potentially safer considering the average user has something like 150 accounts online, and a significant number of those accounts are going to be tied to one’s mobile number.

The full Princeton study is available here (PDF).

In a Twitter discussion last week on ransomware attacks, KrebsOnSecurity noted that virtually all ransomware strains have a built-in failsafe designed to cover the backsides of the malware purveyors: They simply will not install on a Microsoft Windows computer that already has one of many types of virtual keyboards installed — such as Russian or Ukrainian. So many readers had questions in response to the tweet that I thought it was worth a blog post exploring this one weird cyber defense trick.

The Twitter thread came up in a discussion on the ransomware attack against Colonial Pipeline, which earlier this month shut down 5,500 miles of fuel pipe for nearly a week, causing fuel station supply shortages throughout the country and driving up prices. The FBI said the attack was the work of DarkSide, a new-ish ransomware-as-a-service offering that says it targets only large corporations.

DarkSide and other Russian-language affiliate moneymaking programs have long barred their criminal associates from installing malicious software on computers in a host of Eastern European countries, including Ukraine and Russia. This prohibition dates back to the earliest days of organized cybercrime, and it is intended to minimize scrutiny and interference from local authorities.

In Russia, for example, authorities there generally will not initiate a cybercrime investigation against one of their own unless a company or individual within the country’s borders files an official complaint as a victim. Ensuring that no affiliates can produce victims in their own countries is the easiest way for these criminals to stay off the radar of domestic law enforcement agencies.

Possibly feeling the heat from being referenced in President Biden’s Executive Order on cybersecurity this past week, the DarkSide group sought to distance itself from their attack against Colonial Pipeline. In a message posted to its victim shaming blog, DarkSide tried to say it was “apolitical” and that it didn’t wish to participate in geopolitics.

“Our goal is to make money, and not creating problems for society,” the DarkSide criminals wrote last week. “From today we introduce moderation and check each company that our partners want to encrypt to avoid social consequences in the future.”

But here’s the thing: Digital extortion gangs like DarkSide take great care to make their entire platforms geopolitical, because their malware is engineered to work only in certain parts of the world.

DarkSide, like a great many other malware strains, has a hard-coded do-not-install list of countries which are the principal members of the Commonwealth of Independent States (CIS) — former Soviet satellites that all currently have favorable relations with the Kremlin, including Azerbaijan, Belarus, Georgia, Romania, Turkmenistan, Ukraine and Uzbekistan. The full exclusion list in DarkSide (published by Cybereason) is below:

Simply put, countless malware strains will check for the presence of one of these languages on the system, and if they’re detected the malware will exit and fail to install.

[Side note. Many security experts have pointed to connections between the DarkSide and REvil (a.k.a. “Sodinokibi”) ransomware groups. REvil was previously known as GandCrab, and one of the many things GandCrab had in common with REvil was that both programs barred affiliates from infecting victims in Syria. As we can see from the chart above, Syria is also exempted from infections by DarkSide ransomware. And DarkSide itself proved their connection to REvil this past week when it announced it was closing up shop after its servers and bitcoin funds were seized.]

CAVEAT EMPTOR

Will installing one of these languages keep your Windows computer safe from all malware? Absolutely not. There is plenty of malware that doesn’t care where in the world you are. And there is no substitute for adopting a defense-in-depth posture, and avoiding risky behaviors online.

But is there really a downside to taking this simple, free, prophylactic approach? None that I can see, other than perhaps a sinking feeling of capitulation. The worst that could happen is that you accidentally toggle the language settings and all your menu options are in Russian.

If this happens (and the first time it does the experience may be a bit jarring) hit the Windows key and the space bar at the same time; if you have more than one language installed you will see the ability to quickly toggle from one to the other. The little box that pops up when one hits that keyboard combo looks like this:

Cybercriminals are notoriously responsive to defenses which cut into their profitability, so why wouldn’t the bad guys just change things up start ignoring the language check? Well, they certainly can and maybe even will do that (a recent version of DarkSide analyzed by Mandiant did not perform the system language check).

But doing so increases the risk to their personal safety and fortunes by some non-trivial amount, said Allison Nixon, chief research officer at New York City-based cyber investigations firm Unit221B.

Nixon said because of Russia’s unique legal culture, criminal hackers in that country employ these checks to ensure they are only attacking victims outside of the country.

“This is for their legal protection,” Nixon said. “Installing a Cyrillic keyboard, or changing a specific registry entry to say ‘RU’, and so forth, might be enough to convince malware that you are Russian and off limits. This can technically be used as a ‘vaccine’ against Russian malware.”

Nixon said if enough people do this in large numbers, it may in the short term protect some people, but more importantly in the long term it forces Russian hackers to make a choice: Risk losing legal protections, or risk losing income.

“Essentially, Russian hackers will end up facing the same difficulty that defenders in the West must face — the fact that it is very difficult to tell the difference between a domestic machine and a foreign machine masquerading as a domestic one,” she said.

KrebsOnSecurity asked Nixon’s colleague at Unit221B — founder Lance James — what he thought about the efficacy of another anti-malware approach suggested by Twitter followers who chimed in on last week’s discussion: Adding entries to the Windows registry that specify the system is running as a virtual machine (VM). In a bid to stymie analysis by antivirus and security firms, some malware authors have traditionally configured their malware to quit installing if it detects it is running in a virtual environment.

But James said this prohibition is no longer quite so common, particularly since so many organizations have transitioned to virtual environments for everyday use.

“Being a virtual machine doesn’t stop malware like it used to,” James said. “In fact, a lot of the ransomware we’re seeing now is running on VMs.”

But James says he loves the idea of everyone adding a language from the CIS country list so much he’s produced his own clickable two-line Windows batch script that adds a Russian language reference in the specific Windows registry keys that are checked by malware. The script effectively allows one’s Windows PC to look like it has a Russian keyboard installed without actually downloading the added script libraries from Microsoft.

To install a different keyboard language on a Windows 10 computer the old fashioned way, hit the Windows key and X at the same time, then select Settings, and then select “Time and Language.” Select Language, and then scroll down and you should see an option to install another character set. Pick one, and the language should be installed the next time you reboot. Again, if for some reason you need to toggle between languages, Windows+Spacebar is your friend.

The DarkSide ransomware affiliate program responsible for the six-day outage at Colonial Pipeline this week that led to fuel shortages and price spikes across the country is running for the hills. The crime gang announced it was closing up shop after its servers were seized and someone drained the cryptocurrency from an account the group uses to pay affiliates.

“Servers were seized (country not named), money of advertisers and founders was transferred to an unknown account,” reads a message from a cybercrime forum reposted to the Russian OSINT Telegram channel.

“A few hours ago, we lost access to the public part of our infrastructure,” the message continues, explaining the outage affected its victim shaming blog where stolen data is published from victims who refuse to pay a ransom. The outage also took down its payment server and those that supply its distributed denial-of-service feature, which is used to turn up the heat on victims who balk at paying.

“Also, a few hours after the withdrawal, funds from the payment server (ours and clients’) were withdrawn to an unknown address,” the DarkSide admin says.

DarkSide organizers also said they were releasing decryption tools for all of the companies that have been ransomed but which haven’t yet paid.

“After that, you will be free to communicate with them wherever you want in any way you want,” the instructions read.

The DarkSide message includes passages apparently penned by a leader of the REvil ransomware-as-a-service platform. This is interesting because security experts have posited that many of DarkSide’s core members are closely tied to the REvil gang.

The REvil representative said its program was introducing new restrictions on the kinds of organizations that affiliates could hold for ransom, and that henceforth it would be forbidden to attack those in the “social sector” (defined as healthcare and educational institutions) and organizations in the “gov-sector” (state) of any country. Affiliates also will be required to get approval before infecting victims.

The new restrictions came as some Russian cybercrime forums began distancing themselves from ransomware operations altogether. On Thursday, the administrator of the popular Russian forum XSS announced the forum would no longer allow discussion threads about ransomware moneymaking programs.

“There’s too much publicity,” the XSS administrator explained. “Ransomware has gathered a critical mass of nonsense, bullshit, hype, and fuss around it. The word ‘ransomware’ has been put on a par with a number of unpleasant phenomena, such as geopolitical tensions, extortion, and government-backed hacks. This word has become dangerous and toxic.”

In a blog post on the DarkSide closure, cyber intelligence firm Intel 471 said it believes all of these actions can be tied directly to the reaction related to the high-profile ransomware attacks covered by the media this week.

“However, a strong caveat should be applied to these developments: it’s likely that these ransomware operators are trying to retreat from the spotlight more than suddenly discovering the error of their ways,” Intel 471 wrote. “A number of the operators will most likely operate in their own closed-knit groups, resurfacing under new names and updated ransomware variants. Additionally, the operators will have to find a new way to ‘wash’ the cryptocurrency they earn from ransoms. Intel 471 has observed that BitMix, a popular cryptocurrency mixing service used by Avaddon, DarkSide and REvil has allegedly ceased operations. Several apparent customers of the service reported they were unable to access BitMix in the last week.”

Microsoft today released fixes to plug at least 55 security holes in its Windows operating systems and other software. Four of these weaknesses can be exploited by malware and malcontents to seize complete, remote control over vulnerable systems without any help from users. On deck this month are patches to quash a wormable flaw, a creepy wireless bug, and yet another reason to call for the death of Microsoft’s Internet Explorer (IE) web browser.

While May brings about half the normal volume of updates from Microsoft, there are some notable weaknesses that deserve prompt attention, particularly from enterprises. By all accounts, the most pressing priority this month is CVE-2021-31166, a Windows 10 and Windows Server flaw which allows an unauthenticated attacker to remotely execute malicious code at the operating system level. With this weakness, an attacker could compromise a host simply by sending it a specially-crafted packet of data.

“That makes this bug wormable, with even Microsoft calling that out in their write-up,” said Dustin Childs, with Trend Micro’s ZDI program. “Before you pass this aside, Windows 10 can also be configured as a web server, so it is impacted as well. Definitely put this on the top of your test-and-deploy list.”

Kevin Breen from Immersive Labs said the fact that this one is just 0.2 points away from a perfect 10 CVSS score should be enough to identify just how important it is to patch.

“For ransomware operators, this kind of vulnerability is a prime target for exploitation,” Breen said. “Wormable exploits should always be a high priority, especially if they are for services that are designed to be public facing. As this specific exploit would not require any form of authentication, it’s even more appealing for attackers, and any organization using HTTP.sys protocol stack should prioritize this patch.”

Breen also called attention to CVE-2021-26419 — a vulnerability in Internet Explorer 11 — to make the case for why IE needs to stand for “Internet Exploder.” To trigger this vulnerability, a user would have to visit a site that is controlled by the attacker, although Microsoft also recognizes that it could be triggered by embedding ActiveX controls in Office Documents.

“IE needs to die – and I’m not the only one that thinks so,” Breen said. “If you are an organization that has to provide IE11 to support legacy applications, consider enforcing a policy on the users that restricts the domains that can be accessed by IE11 to only those legacy applications. All other web browsing should be performed with a supported browser.”

Another curious bug fixed this month is CVE-2020-24587, described as a “Windows Wireless Networking Information Disclosure Vulnerability.” ZDI’s Childs said this one has the potential to be pretty damaging.

“This patch fixes a vulnerability that could allow an attacker to disclose the contents of encrypted wireless packets on an affected system,” he said. “It’s not clear what the range on such an attack would be, but you should assume some proximity is needed. You’ll also note this CVE is from 2020, which could indicate Microsoft has been working on this fix for some time.”

Microsoft also patched four more security holes its Exchange Server corporate email platform, which recently was besieged by attacks on four other zero-day Exchange flaws that resulted in hundreds of thousands of servers worldwide getting hacked. One of the bugs is credited to Orange Tsai of the DEVCORE research team, who was responsible for disclosing the ProxyLogon Exchange Server vulnerability that was patched in an out-of-band release back in March.

“While none of these flaws are deemed critical in nature, it is a reminder that researchers and attackers are still looking closely at Exchange Server for additional vulnerabilities, so organizations that have yet to update their systems should do so as soon as possible,” said Satnam Narang, staff research engineer at Tenable.

As always, it’s a good idea for Windows users to get in the habit of updating at least once a month, but for regular users (read: not enterprises) it’s usually safe to wait a few days until after the patches are released, so that Microsoft has time to iron out any kinks in the new armor.

But before you update, please make sure you have backed up your system and/or important files. It’s not uncommon for a Windows update package to hose one’s system or prevent it from booting properly, and some updates have been known to erase or corrupt files.

So do yourself a favor and backup before installing any patches. Windows 10 even has some built-in tools to help you do that, either on a per-file/folder basis or by making a complete and bootable copy of your hard drive all at once.

And if you wish to ensure Windows has been set to pause updating so you can back up your files and/or system before the operating system decides to reboot and install patches on its own schedule, see this guide.

If you experience glitches or problems installing any of these patches this month, please consider leaving a comment about it below; there’s a better-than-even chance other readers have experienced the same and may chime in here with some helpful tips.