SMS About Bank Fraud as a Pretext for Voice Phishing

November 10, 2021

Most of us have probably heard the term “smishing” — which is a portmanteau for traditional phishing scams sent through SMS text messages. Smishing messages usually include a link to a site that spoofs a popular bank and tries to siphon personal information. But increasingly, phishers are turning to a hybrid form of smishing — blasting out linkless text messages about suspicious bank transfers as a pretext for immediately calling and scamming anyone who responds via text.

KrebsOnSecurity recently heard from a reader who said his daughter received an SMS that said it was from her bank, and inquired whether she’d authorized a $5,000 payment from her account. The message said she should reply “Yes” or “No,” or 1 to decline future fraud alerts.

Since this seemed like a reasonable and simple request — and she indeed had an account at the bank in question — she responded, “NO.”

Seconds later, her mobile phone rang.

“When she replied ‘no,’ someone called immediately, and the caller ID said ‘JP Morgan Chase’,” reader Kris Stevens told KrebsOnSecurity. “The person on the phone said they were from the fraud department and they needed to help her secure her account but needed information from her to make sure they were talking to the account owner and not the scammer.”

Thankfully, Stevens said his daughter had honored the gold rule regarding incoming phone calls about fraud: When In Doubt, Hang up, Look up, and Call Back.

“She knows the drill so she hung up and called Chase, who confirmed they had not called her,” he said. “What was different about this was it was all very smooth. No foreign accents, the pairing of the call with the text message, and the fact that she does have a Chase account.”

The remarkable aspect of these phone-based phishing scams is typically the attackers never even try to log in to the victim’s bank account. The entirety of the scam takes place over the phone.

We don’t know what the fraudsters behind this clever hybrid SMS/voice phishing scam intended to do with the information they might have coaxed from Stevens’ daughter. But in previous stories and reporting on voice phishing schemes, the fraudsters used the phished information to set up new financial accounts in the victim’s name, which they then used to receive and forward large wire transfers of stolen funds.

Even many security-conscious people tend to focus on protecting their online selves, while perhaps discounting the threat from less technically sophisticated phone-based scams. In 2020 I told the story of “Mitch” — the tech-savvy Silicon Valley executive who got voice phished after he thought he’d turned the tables on the scammers.

Unlike Stevens’ daughter, Mitch didn’t hang up with the suspected scammers. Rather, he put them on hold. Then Mitch called his bank on the other line and asked if their customer support people were in fact engaged in a separate conversation with him over the phone.

The bank replied that they were indeed speaking to the same customer on a different line at that very moment. Feeling better, Mitch got back on the line with the scammers. What Mitch couldn’t have known at that point was that a member of the fraudster’s team simultaneously was impersonating him on the phone with the bank’s customer service people.

So don’t be Mitch. Don’t try to outsmart the crooks. Just remember this anti-fraud mantra, and maybe repeat it a few times in front of your friends and family: When in doubt, hang up, look up, and call back. If you believe the call might be legitimate, look up the number of the organization supposedly calling you, and call them back.

And I suppose the same time-honored advice about not replying to spam email goes doubly for unsolicited text messages: When in doubt, it’s best not to respond.

Microsoft Patch Tuesday, November 2021 Edition

November 9, 2021

Microsoft Corp. today released updates to quash at least 55 security bugs in its Windows operating systems and other software. Two of the patches address vulnerabilities that are already being used in active attacks online, and four of the flaws were disclosed publicly before today — potentially giving adversaries a head start in figuring out how to exploit them.

Among the zero-day bugs is CVE-2021-42292, a “security feature bypass” problem with Microsoft Excel versions 2013-2021 that could allow attackers to install malicious code just by convincing someone to open a booby-trapped Excel file (Microsoft says Mac versions of Office are also affected, but several places are reporting that Office for Mac security updates aren’t available yet).

Microsoft’s revised, more sparse security advisories don’t offer much detail on what exactly is being bypassed in Excel with this flaw. But Dustin Childs over at Trend Micro’s Zero Day Initiative says the vulnerability is likely due to loading code that should be limited by a user prompt — such as a warning about external content or scripts — but for whatever reason that prompt does not appear, thus bypassing the security feature.

The other critical flaw patched today that’s already being exploited in the wild is CVE-2021-42321, yet another zero-day in Microsoft Exchange Server. You may recall that earlier this year a majority of the world’s organizations running Microsoft Exchange Servers were hit with four zero-day attacks that let thieves install backdoors and siphon email. Continue reading

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REvil Ransom Arrest, $6M Seizure, and $10M Reward

November 8, 2021

The U.S. Department of Justice today announced the arrest of Ukrainian man accused of deploying ransomware on behalf of the REvil ransomware gang, a Russian-speaking cybercriminal collective that has extorted hundreds of millions from victim organizations. The DOJ also said it had seized $6.1 million in cryptocurrency sent to another REvil affiliate, and that the U.S. Department of State is now offering up to $10 million for the name or location any key REvil leaders, and up to $5 million for information on REvil affiliates.

If it sounds unlikely that a normal Internet user could make millions of dollars unmasking the identities of REvil gang members, take heart and consider that the two men indicted as part this law enforcement action do not appear to have done much to separate their cybercriminal identities from their real-life selves.

Exhibit #1: Yaroslav Vasinskyi, the 22-year-old Ukrainian national accused of being REvil Affiliate #22. Vasinskyi was arrested Oct. 8 in Poland, which maintains an extradition treaty with the United States. Prosecutors say Vasinskyi was involved in a number of REvil ransomware attacks, including the July 2021 attack against Kaseya, a Miami-based company whose products help system administrators manage large networks remotely.

Yaroslav Vasinksyi’s Vkontakte profile reads “If they tell you nasty things about me, believe every word.”

According to his indictment (PDF), Vasinskyi used a variety of hacker handles, including “Profcomserv” — the nickname behind an online service that floods phone numbers with junk calls for a fee. Prosecutors say Vasinskyi also used the monikers  “Yarik45,” and “Yaroslav2468.”

These last two nicknames correspond to accounts on several top cybercrime forums way back in 2013, where a user named “Yaroslav2468” registered using the email address yarik45@gmail.com.

That email address was used to register an account at Vkontakte (the Russian version of Facebook/Meta) under the profile name of “Yaroslav ‘sell the blood of css’ Vasinskyi.” Vasinskyi’s Vkontakte profile says his current city as of Oct. 3 was Lublin, Poland. Perhaps tauntingly, Vasinskyi’s profile page also lists the FBI’s 1-800 tip line as his contact phone number. He’s now in custody in Poland, awaiting extradition to the United States.

Exhibit #2: Yevgeniy Igorevich Polyanin, the 28-year-old Russian national who is alleged to be REvil Affiliate #23. The DOJ said it seized $6.1 million in funds traceable to alleged ransom payments received by Polyanin, and that the defendant had been involved in REvil ransomware attacks on multiple U.S. victim organizations.

The FBI’s wanted poster for Polyanin.

Polyanin’s indictment (PDF) says he also favored numerous hacker handles, including LK4D4, Damnating, Damn2life, Noolleds, and Antunpitre. Some of these nicknames go back more than a decade on Russian cybercrime forums, many of which have been hacked and relieved of their user databases over the years.

Among those was carder[.]su, and that forum’s database says a user by the name “Damnating” registered with the forum in 2008 using the email address damnating@yandex.ru. Sure enough, there is a Vkontakte profile tied to that email address under the name “Yevgeniy ‘damn’ Polyanin” from Barnaul, a city in the southern Siberian region of Russia. Continue reading

‘Tis the Season for the Wayward Package Phish

November 4, 2021

The holiday shopping season always means big business for phishers, who tend to find increased success this time of year with a lure about a wayward package that needs redelivery. Here’s a look at a fairly elaborate SMS-based phishing scam that spoofs FedEx in a bid to extract personal and financial information from unwary recipients.

One of dozens of FedEx-themed phishing sites currently being advertised via SMS spam.

Louis Morton, a security professional based in Fort Worth, Texas, forwarded an SMS phishing or “smishing” message sent to his wife’s mobile device that indicated a package couldn’t be delivered.

“It is a nearly perfect attack vector at this time of year,” Morton said. “A link was included, implying that the recipient could reschedule delivery.”

Attempting to visit the domain in the phishing link — o001cfedeex[.]com — from a desktop web browser redirects the visitor to a harmless page with ads for car insurance quotes. But by loading it in a mobile device (or by mimicking one using developer tools), we can see the intended landing page pictured in the screenshot to the right — returns-fedex[.]com.

Blocking non-mobile users from visiting the domain can help minimize scrutiny of the site from non-potential victims, such as security researchers, and thus potentially keep the scam site online longer.

Clicking “Schedule new delivery” brings up a page that requests your name, address, phone number and date of birth. Those who click “Next Step” after providing that information are asked to add a payment card to cover the $2.20 “redelivery fee.” Continue reading

The ‘Groove’ Ransomware Gang Was a Hoax

November 2, 2021

A number of publications in September warned about the emergence of “Groove,” a new ransomware group that called on competing extortion gangs to unite in attacking U.S. government interests online. It now appears that Groove was all a big hoax designed to toy with security firms and journalists.

“An appeal to business brothers!” reads the Oct. 22 post from Groove calling for attacks on the United States government sector.

Groove was first announced Aug. 22 on RAMP, a new and fairly exclusive Russian-language darknet cybercrime forum.

“GROOVE is first and foremost an aggressive financially motivated criminal organization dealing in industrial espionage for about two years,” wrote RAMP’s administrator “Orange” in a post asking forum members to compete in a contest for designing a website for the new group. “Let’s make it clear that we don’t do anything without a reason, so at the end of the day, it’s us who will benefit most from this contest.”

According to a report published by McAfee, Orange launched RAMP to appeal to ransomware-related threat actors who were were ousted from major cybercrime forums for being too toxic, or to cybercriminals who complained of being short-changed or stiffed altogether by different ransomware affiliate programs.

The report said RAMP was the product of a dispute between members of the Babuk ransomware gang, and that its members likely had connections to another ransomware group called BlackMatter.

“[McAfee] believes, with high confidence, that the Groove gang is a former affiliate or subgroup of the Babuk gang, who are willing to collaborate with other parties, as long as there is financial gain for them,” the report said. “Thus, an affiliation with the BlackMatter gang is likely.”

In the first week of September, Groove posted on its darknet blog nearly 500,000 login credentials for customers of Fortinet VPN products, usernames and passwords that could be used to remotely connect to vulnerable systems. Fortinet said the credentials were collected from systems that hadn’t yet implemented a patch issued in May 2019.

Some security experts said the post of the Fortinet VPN usernames and passwords was aimed at drawing new affiliates to Groove. But it seems more likely the credentials were posted to garner the attention of security researchers and journalists.

Sometime in the last week, Groove’s darknet blog disappeared. In a post on the Russian cybercrime forum XSS, an established cybercrook using the handle “Boriselcin” explained that Groove was little more than a pet project to screw with the media and security industry.

“For those who don’t understand what’s going on: I set up a fake Groove Gang and named myself a gang,” Boriselcin wrote. The rest of the post reads:

“They ate it up, I dumped 500k old Fortinet [access credentials] that no one needed and they ate it up. I say that I am going to target the U.S. government sector and they eat it up. Few journalists realized that this was all a show, a fake, and a scam! And my respect goes out to those who figured it out. I don’t even know what to do now with this blog with a ton of traffic. Maybe sell it? Now I just need to start writing [the article], but I can’t start writing it without checking everything.”

A review of Boriselcin’s recent postings on XSS indicate he has been planning this scheme for several months. On Sept. 13, Boriselcin posted that “several topics are ripening,” and that he intended to publish an article about duping the media and security firms.

“Manipulation of large information security companies and the media through a ransom blog,” he wrote. “It’s so funny to read Twitter and the news these days 🙂 But the result is great so far. Triggering the directors of information security companies. We fuck the supply chain of the information security office.”

Image: @nokae8

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‘Trojan Source’ Bug Threatens the Security of All Code

November 1, 2021

Virtually all compilers — programs that transform human-readable source code into computer-executable machine code — are vulnerable to an insidious attack in which an adversary can introduce targeted vulnerabilities into any software without being detected, new research released today warns. The vulnerability disclosure was coordinated with multiple organizations, some of whom are now releasing updates to address the security weakness.

Researchers with the University of Cambridge discovered a bug that affects most computer code compilers and many software development environments. At issue is a component of the digital text encoding standard Unicode, which allows computers to exchange information regardless of the language used. Unicode currently defines more than 143,000 characters across 154 different language scripts (in addition to many non-script character sets, such as emojis).

Specifically, the weakness involves Unicode’s bi-directional or “Bidi” algorithm, which handles displaying text that includes mixed scripts with different display orders, such as Arabic — which is read right to left — and English (left to right).

But computer systems need to have a deterministic way of resolving conflicting directionality in text. Enter the “Bidi override,” which can be used to make left-to-right text read right-to-left, and vice versa.

“In some scenarios, the default ordering set by the Bidi Algorithm may not be sufficient,” the Cambridge researchers wrote. “For these cases, Bidi override control characters enable switching the display ordering of groups of characters.”

Bidi overrides enable even single-script characters to be displayed in an order different from their logical encoding. As the researchers point out, this fact has previously been exploited to disguise the file extensions of malware disseminated via email.

Here’s the problem: Most programming languages let you put these Bidi overrides in comments and strings. This is bad because most programming languages allow comments within which all text — including control characters — is ignored by compilers and interpreters. Also, it’s bad because most programming languages allow string literals that may contain arbitrary characters, including control characters.

“So you can use them in source code that appears innocuous to a human reviewer [that] can actually do something nasty,” said Ross Anderson, a professor of computer security at Cambridge and co-author of the research. “That’s bad news for projects like Linux and Webkit that accept contributions from random people, subject them to manual review, then incorporate them into critical code. This vulnerability is, as far as I know, the first one to affect almost everything.”

The research paper, which dubbed the vulnerability “Trojan Source,” notes that while both comments and strings will have syntax-specific semantics indicating their start and end, these bounds are not respected by Bidi overrides. From the paper:

“Therefore, by placing Bidi override characters exclusively within comments and strings, we can smuggle them into source code in a manner that most compilers will accept. Our key insight is that we can reorder source code characters in such a way that the resulting display order also represents syntactically valid source code.”

“Bringing all this together, we arrive at a novel supply-chain attack on source code. By injecting Unicode Bidi override characters into comments and strings, an adversary can produce syntactically-valid source code in most modern languages for which the display order of characters presents logic that diverges from the real logic. In effect, we anagram program A into program B.”

Anderson said such an attack could be challenging for a human code reviewer to detect, as the rendered source code looks perfectly acceptable.

“If the change in logic is subtle enough to go undetected in subsequent testing, an adversary could introduce targeted vulnerabilities without being detected,” he said.

Equally concerning is that Bidi override characters persist through the copy-and-paste functions on most modern browsers, editors, and operating systems.

“Any developer who copies code from an untrusted source into a protected code base may inadvertently introduce an invisible vulnerability,” Anderson told KrebsOnSecurity. “Such code copying is a significant source of real-world security exploits.”

Image: XKCD.com/2347/

Matthew Green, an associate professor at the Johns Hopkins Information Security Institute, said the Cambridge research clearly shows that most compilers can be tricked with Unicode into processing code in a different way than a reader would expect it to be processed.

“Before reading this paper, the idea that Unicode could be exploited in some way wouldn’t have surprised me,” Green told KrebsOnSecurity. “What does surprise me is how many compilers will happily parse Unicode without any defenses, and how effective their right-to-left encoding technique is at sneaking code into codebases. That’s a really clever trick I didn’t even know was possible. Yikes.”

Green said the good news is that the researchers conducted a widespread vulnerability scan, but were unable to find evidence that anyone was exploiting this. Yet.

“The bad news is that there were no defenses to it, and now that people know about it they might start exploiting it,” Green said. “Hopefully compiler and code editor developers will patch this quickly! But since some people don’t update their development tools regularly there will be some risk for a while at least.” Continue reading

Zales.com Leaked Customer Data, Just Like Sister Firms Jared, Kay Jewelers Did in 2018

October 28, 2021

In December 2018, bling vendor Signet Jewelers fixed a weakness in their Kay Jewelers and Jared websites that exposed the order information for all of their online customers. This week, Signet subsidiary Zales.com updated its website to remediate a nearly identical customer data exposure.

Last week, KrebsOnSecurity heard from a reader who was browsing Zales.com and suddenly found they were looking at someone else’s order information on the website, including their name, billing address, shipping address, phone number, email address, items and total amount purchased, delivery date, tracking link, and the last four digits of the customer’s credit card number.

The reader noticed that the link for the order information she’d stumbled on included a lengthy numeric combination that — when altered — would produce yet another customer’s order information.

When the reader failed to get an immediate response from Signet, KrebsOnSecurity contacted the company. In a written response, Signet said, “A concern was brought to our attention by an IT professional. We addressed it swiftly, and upon review we found no misuse or negative impact to any systems or customer data.”

Their statement continues:

“As a business principle we make consumer information protection the highest priority, and proactively initiate independent and industry-leading security testing. As a result, we exceed industry benchmarks on data protection maturity. We always appreciate it when consumers reach out to us with feedback, and have committed to further our efforts on data protection maturity.”

When Signet fixed similar weaknesses with its Jared and Kay websites back in 2018, the reader who found and reported that data exposure said his mind quickly turned to the various ways crooks might exploit access to customer order information.

“My first thought was they could track a package of jewelry to someone’s door and swipe it off their doorstep,” said Brandon Sheehy, a Dallas-based Web developer. “My second thought was that someone could call Jared’s customers and pretend to be Jared, reading the last four digits of the customer’s card and saying there’d been a problem with the order, and if they could get a different card for the customer they could run it right away and get the order out quickly. That would be a pretty convincing scam. Or just targeted phishing attacks.” Continue reading

FBI Raids Chinese Point-of-Sale Giant PAX Technology

October 26, 2021

U.S. federal investigators today raided the Florida offices of PAX Technology, a Chinese provider of point-of-sale devices used by millions of businesses and retailers globally. KrebsOnSecurity has learned the raid is tied to reports that PAX’s systems may have been involved in cyberattacks on U.S. and E.U. organizations.

FBI agents entering PAX Technology offices in Jacksonville today. Source: WOKV.com.

Headquartered in Shenzhen, China, PAX Technology Inc. has more than 60 million point-of-sale terminals in use throughout 120 countries. Earlier today, Jacksonville, Fla. based WOKV.com reported that agents with the FBI and Department of Homeland Security (DHS) had raided a local PAX Technology warehouse.

In an official statement, investigators told WOKV only that they were executing a court-authorized search at the warehouse as a part of a federal investigation, and that the inquiry included the Department of Customs and Border Protection and the Naval Criminal Investigative Services (NCIS). The FBI has not responded to requests for comment.

Several days ago, KrebsOnSecurity heard from a trusted source that the FBI began investigating PAX after a major U.S. payment processor started asking questions about unusual network packets originating from the company’s payment terminals.

According to that source, the payment processor found that the PAX terminals were being used both as a malware “dropper” — a repository for malicious files — and as “command-and-control” locations for staging attacks and collecting information.

“FBI and MI5 are conducting an intensive investigation into PAX,” the source said. “A major US payment processor began asking questions about network packets originating from PAX terminals and were not given any good answers.”

KrebsOnSecurity reached out to PAX Technology’s CEO on Sunday. The company has not yet responded to requests for comment.

The source said two major financial providers — one in the United States and one in the United Kingdom — had already begun pulling PAX terminals from their payment infrastructure, a claim that was verified by two different sources. Continue reading

Conti Ransom Gang Starts Selling Access to Victims

October 25, 2021

The Conti ransomware affiliate program appears to have altered its business plan recently. Organizations infected with Conti’s malware who refuse to negotiate a ransom payment are added to Conti’s victim shaming blog, where confidential files stolen from victims may be published or sold. But sometime over the past 48 hours, the cybercriminal syndicate updated its victim shaming blog to indicate that it is now selling access to many of the organizations it has hacked.

A redacted screenshot of the Conti News victim shaming blog.

“We are looking for a buyer to access the network of this organization and sell data from their network,” reads the confusingly worded message inserted into multiple recent victim listings on Conti’s shaming blog.

It’s unclear what prompted the changes, or what Conti hopes to gain from the move. It’s also not obvious why they would advertise having hacked into companies if they plan on selling that access to extract sensitive data going forward. Conti did not respond to requests for comment.

“I wonder if they are about to close down their operation and want to sell data or access from an in-progress breach before they do,” said Fabian Wosar, chief technology officer at computer security firm Emsisoft. “But it’s somewhat stupid to do it that way as you will alert the companies that they have a breach going on.”

The unexplained shift comes as policymakers in the United States and Europe are moving forward on efforts to disrupt some of the top ransomware gangs. Reuters recently reported that the U.S. government was behind an ongoing hacking operation that penetrated the computer systems of REvil, a ransomware affiliate group that experts say is about as aggressive and ruthless as Conti in dealing with victims. What’s more, REvil was among the first ransomware groups to start selling its victims’ data.

REvil’s darknet victim shaming site remains offline. In response, a representative for the Conti gang posted a long screed on Oct. 22 to a Russian language hacking forum denouncing the attack on REvil as the “unilateral, extraterritorial, and bandit-mugging behavior of the United States in world affairs.” Continue reading

Missouri Governor Vows to Prosecute St. Louis Post-Dispatch for Reporting Security Vulnerability

October 14, 2021

On Wednesday, the St. Louis Post-Dispatch ran a story about how its staff discovered and reported a security vulnerability in a Missouri state education website that exposed the Social Security numbers of 100,000 elementary and secondary teachers. In a press conference this morning, Missouri Gov. Mike Parson (R) said fixing the flaw could cost the state $50 million, and vowed his administration would seek to prosecute and investigate the “hackers” and anyone who aided the publication in its “attempt to embarrass the state and sell headlines for their news outlet.”

Missouri Gov. Mike Parson (R), vowing to prosecute the St. Louis Post-Dispatch for reporting a security vulnerability that exposed teacher SSNs.

The Post-Dispatch says it discovered the vulnerability in a web application that allowed the public to search teacher certifications and credentials, and that more than 100,000 SSNs were available. The Missouri state Department of Elementary and Secondary Education (DESE) reportedly removed the affected pages from its website Tuesday after being notified of the problem by the publication (before the story on the flaw was published).

The newspaper said it found that teachers’ Social Security numbers were contained in the HTML source code of the pages involved. In other words, the information was available to anyone with a web browser who happened to also examine the site’s public code using Developer Tools or simply right-clicking on the page and viewing the source code.

The Post-Dispatch reported that it wasn’t immediately clear how long the Social Security numbers and other sensitive information had been vulnerable on the DESE website, nor was it known if anyone had exploited the flaw.

But in a press conference Thursday morning, Gov. Parson said he would seek to prosecute and investigate the reporter and the region’s largest newspaper for “unlawfully” accessing teacher data.

“This administration is standing up against any and all perpetrators who attempt to steal personal information and harm Missourians,” Parson said. “It is unlawful to access encoded data and systems in order to examine other peoples’ personal information. We are coordinating state resources to respond and utilize all legal methods available. My administration has notified the Cole County prosecutor of this matter, the Missouri State Highway Patrol’s Digital Forensics Unit will also be conducting an investigation of all of those involved. This incident alone may cost Missouri taxpayers as much as $50 million.”

While threatening to prosecute the reporters to the fullest extent of the law, Parson sought to downplay the severity of the security weakness, saying the reporter only unmasked three Social Security numbers, and that “there was no option to decode Social Security numbers for all educators in the system all at once.”

“The state is committed to bringing to justice anyone who hacked our systems or anyone who aided them to do so,” Parson continued. “A hacker is someone who gains unauthorized access to information or content. This individual did not have permission to do what they did. They had no authorization to convert or decode, so this was clearly a hack.” Continue reading