Ransomware


27
Jan 21

Arrest, Seizures Tied to Netwalker Ransomware

U.S. and Bulgarian authorities this week seized the darkweb site used by the NetWalker ransomware cybercrime group to publish data stolen from its victims. In connection with the seizure, a Canadian national suspected of extorting more than $27 million through the spreading of NetWalker was charged in a Florida court.

The victim shaming site maintained by the NetWalker ransomware group, after being seized by authorities this week.

NetWalker is a ransomware-as-a-service crimeware product in which affiliates rent access to the continuously updated malware code in exchange for a percentage of any funds extorted from victims. The crooks behind NetWalker used the now-seized website to publish personal and proprietary data stolen from their prey, as part of a public pressure campaign to convince victims to pay up.

NetWalker has been among the most rapacious ransomware strains, hitting at least 305 victims from 27 countries — the majority in the United States, according to Chainalysis, a company that tracks the flow virtual currency payments.

“Chainalysis has traced more than $46 million worth of funds in NetWalker ransoms since it first came on the scene in August 2019,” the company said in a blog post detailing its assistance with the investigation. “It picked up steam in mid-2020, growing the average ransom to $65,000 last year, up from $18,800 in 2019.”

Image: Chainalysis

In a statement on the seizure, the Justice Department said the NetWalker ransomware has impacted numerous victims, including companies, municipalities, hospitals, law enforcement, emergency services, school districts, colleges, and universities. For example, the University of California, San Francisco paid $1.14 million last summer in exchange for a digital key needed to unlock files encrypted by the ransomware.

“Attacks have specifically targeted the healthcare sector during the COVID-19 pandemic, taking advantage of the global crisis to extort victims,” the DOJ said.

U.S. prosecutors say one of NetWalker’s top affiliates was Sebastien Vachon-Desjardins, of Gatineau, in Ottawa, Canada. An indictment unsealed today in Florida alleges Vachon-Desjardins obtained at least $27.6 million from the scheme.

The DOJ’s media advisory doesn’t mention the defendant’s age, but a 2015 report in the Gatineau local news website ledroit.com suggests this may not be his first offense. According to the story, a then-27-year-old Sebastien Vachon-Desjardins was sentenced to more than three years in prison for drug trafficking: He was reportedly found in possession of more than 50,000 methamphetamine tablets. Continue reading →


27
Jan 21

International Action Targets Emotet Crimeware

Authorities across Europe on Tuesday said they’d seized control over Emotet, a prolific malware strain and cybercrime-as-service operation. Investigators say the action could help quarantine more than a million Microsoft Windows systems currently compromised with malware tied to Emotet infections.

First surfacing in 2014, Emotet began as a banking trojan, but over the years it has evolved into one of the more aggressive platforms for spreading malware that lays the groundwork for ransomware attacks.

In a statement published Wednesday morning on an action dubbed “Operation Ladybird,” the European police agency Europol said the investigation involved authorities in the Netherlands, Germany, United States, the United Kingdom, France, Lithuania, Canada and Ukraine.

“The EMOTET infrastructure essentially acted as a primary door opener for computer systems on a global scale,” Europol said. “Once this unauthorised access was established, these were sold to other top-level criminal groups to deploy further illicit activities such data theft and extortion through ransomware.”

Experts say Emotet is a pay-per-install botnet that is used by several distinct cybercrime groups to deploy secondary malware — most notably the ransomware strain Ryuk and Trickbot, a powerful banking trojan. It propagates mainly via malicious links and attachments sent through compromised email accounts, blasting out tens of thousands of malware-laced missives daily.

Emotet relies on several hierarchical tiers of control servers that communicate with infected systems. Those controllers coordinate the dissemination of second-stage malware and the theft of passwords and other data, and their distributed nature is designed to make the crimeware infrastructure more difficult to dismantle or commandeer.

In a separate statement on the malware takeover, the Dutch National police said two of the three primary servers were located in the Netherlands.

“A software update is placed on the Dutch central servers for all infected computer systems,” the Dutch authorities wrote. “All infected computer systems will automatically retrieve the update there, after which the Emotet infection will be quarantined. Simultaneous action in all the countries concerned was necessary to be able to effectively dismantle the network and thwart any reconstruction.” Continue reading →


10
Dec 20

Payment Processing Giant TSYS: Ransomware Incident “Immaterial” to Company

Payment card processing giant TSYS suffered a ransomware attack earlier this month. Since then reams of data stolen from the company have been posted online, with the attackers promising to publish more in the coming days. But the company says the malware did not jeopardize card data, and that the incident was limited to administrative areas of its business.

Headquartered in Columbus, Ga., Total System Services Inc. (TSYS) is the third-largest third-party payment processor for financial institutions in North America, and a major processor in Europe.

TSYS provides payment processing services, merchant services and other payment solutions, including prepaid debit cards and payroll cards. In 2019, TSYS was acquired by financial services firm Global Payments Inc. [NYSE:GPN].

On December 8, the cybercriminal gang responsible for deploying the Conti ransomware strain (also known as “Ryuk“) published more than 10 gigabytes of data that it claimed to have removed from TSYS’s networks.

Conti is one of several cybercriminal groups that maintains a blog which publishes data stolen from victims in a bid to force the negotiation of ransom payments. The gang claims the data published so far represents just 15 percent of the information it offloaded from TSYS before detonating its ransomware inside the company.

In a written response to requests for comment, TSYS said the attack did not affect systems that handle payment card processing.

“We experienced a ransomware attack involving systems that support certain corporate back office functions of a legacy TSYS merchant business,” TSYS said. “We immediately contained the suspicious activity and the business is operating normally.” Continue reading →


10
Nov 20

Ransomware Group Turns to Facebook Ads

It’s bad enough that many ransomware gangs now have blogs where they publish data stolen from companies that refuse to make an extortion payment. Now, one crime group has started using hacked Facebook accounts to run ads publicly pressuring their ransomware victims into paying up.

On the evening of Monday, Nov. 9, an ad campaign apparently taken out by the Ragnar Locker Team began appearing on Facebook. The ad was designed to turn the screws to the Italian beverage vendor Campari Group, which acknowledged on Nov. 3 that its computer systems had been sidelined by a malware attack.

On Nov. 6, Campari issued a follow-up statement saying “at this stage, we cannot completely exclude that some personal and business data has been taken.”

“This is ridiculous and looks like a big fat lie,” reads the Facebook ad campaign from the Ragnar crime group. “We can confirm that confidential data was stolen and we talking about huge volume of data.”

The ad went on to say Ragnar Locker Team had offloaded two terabytes of information and would give the Italian firm until 6 p.m. EST today (Nov. 10) to negotiate an extortion payment in exchange for a promise not to publish the stolen files.

The Facebook ad blitz was paid for by Hodson Event Entertainment, an account tied to Chris Hodson, a deejay based in Chicago. Contacted by KrebsOnSecurity, Hodson said his Facebook account indeed was hacked, and that the attackers had budgeted $500 for the entire campaign.

“I thought I had two-step verification turned on for all my accounts, but now it looks like the only one I didn’t have it set for was Facebook,” Hodson said.

Hodson said a review of his account shows the unauthorized campaign reached approximately 7,150 Facebook users, and generated 770 clicks, with a cost-per-result of 21 cents. Of course, it didn’t cost the ransomware group anything. Hodson said Facebook billed him $35 for the first part of the campaign, but apparently detected the ads as fraudulent sometime this morning before his account could be billed another $159 for the campaign. Continue reading →


4
Nov 20

Why Paying to Delete Stolen Data is Bonkers

Companies hit by ransomware often face a dual threat: Even if they avoid paying the ransom and can restore things from scratch, about half the time the attackers also threaten to release sensitive stolen data unless the victim pays for a promise to have the data deleted. Leaving aside the notion that victims might have any real expectation the attackers will actually destroy the stolen data, new research suggests a fair number of victims who do pay up may see some or all of the stolen data published anyway.

The findings come in a report today from Coveware, a company that specializes in helping firms recover from ransomware attacks. Coveware says nearly half of all ransomware cases now include the threat to release exfiltrated data.

“Previously, when a victim of ransomware had adequate backups, they would just restore and go on with life; there was zero reason to even engage with the threat actor,” the report observes. “Now, when a threat actor steals data, a company with perfectly restorable backups is often compelled to at least engage with the threat actor to determine what data was taken.”

Coveware said it has seen ample evidence of victims seeing some or all of their stolen data published after paying to have it deleted; in other cases, the data gets published online before the victim is even given a chance to negotiate a data deletion agreement.

“Unlike negotiating for a decryption key, negotiating for the suppression of stolen data has no finite end,” the report continues. “Once a victim receives a decryption key, it can’t be taken away and does not degrade with time. With stolen data, a threat actor can return for a second payment at any point in the future. The track records are too short and evidence that defaults are selectively occurring is already collecting.”

Image: Coveware Q3 2020 report.

The company said it advises clients never to pay a data deletion ransom, but rather to engage competent privacy attorneys, perform an investigation into what data was stolen, and notify any affected customers according to the advice of counsel and application data breach notification laws.

Fabian Wosar, chief technology officer at computer security firm Emsisoft, said ransomware victims often acquiesce to data publication extortion demands when they are trying to prevent the public from learning about the breach.

“The bottom line is, ransomware is a business of hope,” Wosar said. “The company doesn’t want the data to be dumped or sold. So they pay for it hoping the threat actor deletes the data. Technically speaking, whether they delete the data or not doesn’t matter from a legal point of view. The data was lost at the point when it was exfiltrated.”

Ransomware victims who pay for a digital key to unlock servers and desktop systems encrypted by the malware also are relying on hope, Wosar said, because it’s also not uncommon that a decryption key fails to unlock some or all of the infected machines.

“When you look at a lot of ransom notes, you can actually see groups address this very directly and have texts that say stuff along the lines of, Yeah, you are fucked now. But if you pay us, everything can go back to before we fucked you.'”


28
Oct 20

FBI, DHS, HHS Warn of Imminent, Credible Ransomware Threat Against U.S. Hospitals

On Monday, Oct. 26, KrebsOnSecurity began following up on a tip from a reliable source that an aggressive Russian cybercriminal gang known for deploying ransomware was preparing to disrupt information technology systems at hundreds of hospitals, clinics and medical care facilities across the United States. Today, officials from the FBI and the U.S. Department of Homeland Security hastily assembled a conference call with healthcare industry executives warning about an “imminent cybercrime threat to U.S. hospitals and healthcare providers.”

The agencies on the conference call, which included the U.S. Department of Health and Human Services (HHS), warned participants about “credible information of an increased and imminent cybercrime threat to US hospitals and healthcare providers.”

The agencies said they were sharing the information “to provide warning to healthcare providers to ensure that they take timely and reasonable precautions to protect their networks from these threats.”

The warning came less than two days after this author received a tip from Alex Holden, founder of Milwaukee-based cyber intelligence firm Hold Security. Holden said he saw online communications this week between cybercriminals affiliated with a Russian-speaking ransomware group known as Ryuk in which group members discussed plans to deploy ransomware at more than 400 healthcare facilities in the U.S.

One participant on the government conference call today said the agencies offered few concrete details of how healthcare organizations might better protect themselves against this threat actor or purported malware campaign.

“They didn’t share any IoCs [indicators of compromise], so it’s just been ‘patch your systems and report anything suspicious’,” said a healthcare industry veteran who sat in on the discussion.

However, others on the call said IoCs may be of little help for hospitals that have already been infiltrated by Ryuk. That’s because the malware infrastructure used by the Ryuk gang is often unique to each victim, including everything from the Microsoft Windows executable files that get dropped on the infected hosts to the so-called “command and control” servers used to transmit data between and among compromised systems.

Nevertheless, cybersecurity incident response firm Mandiant today released a list of domains and Internet addresses used by Ryuk in previous attacks throughout 2020 and up to the present day. Mandiant refers to the group by the threat actor classification “UNC1878,” and aired a webcast today detailing some of Ryuk’s latest exploitation tactics.

Charles Carmakal, senior vice president for Mandiant, told Reuters that UNC1878 is one of most brazen, heartless, and disruptive threat actors he’s observed over the course of his career.

“Multiple hospitals have already been significantly impacted by Ryuk ransomware and their networks have been taken offline,” Carmakal said. Continue reading →


28
Oct 20

Security Blueprints of Many Companies Leaked in Hack of Swedish Firm Gunnebo

In March 2020, KrebsOnSecurity alerted Swedish security giant Gunnebo Group that hackers had broken into its network and sold the access to a criminal group which specializes in deploying ransomware. In August, Gunnebo said it had successfully thwarted a ransomware attack, but this week it emerged that the intruders stole and published online tens of thousands of sensitive documents — including schematics of client bank vaults and surveillance systems.

The Gunnebo Group is a Swedish multinational company that provides physical security to a variety of customers globally, including banks, government agencies, airports, casinos, jewelry stores, tax agencies and even nuclear power plants. The company has operations in 25 countries, more than 4,000 employees, and billions in revenue annually.

Acting on a tip from Milwaukee, Wis.-based cyber intelligence firm Hold Security, KrebsOnSecurity in March told Gunnebo about a financial transaction between a malicious hacker and a cybercriminal group which specializes in deploying ransomware. That transaction included credentials to a Remote Desktop Protocol (RDP) account apparently set up by a Gunnebo Group employee who wished to access the company’s internal network remotely.

Five months later, Gunnebo disclosed it had suffered a cyber attack targeting its IT systems that forced the shutdown of internal servers. Nevertheless, the company said its quick reaction prevented the intruders from spreading the ransomware throughout its systems, and that the overall lasting impact from the incident was minimal.

Earlier this week, Swedish news agency Dagens Nyheter confirmed that hackers recently published online at least 38,000 documents stolen from Gunnebo’s network. Linus Larsson, the journalist who broke the story, says the hacked material was uploaded to a public server during the second half of September, and it is not known how many people may have gained access to it.

Larsson quotes Gunnebo CEO Stefan Syrén saying the company never considered paying the ransom the attackers demanded in exchange for not publishing its internal documents. What’s more, Syrén seemed to downplay the severity of the exposure.

“I understand that you can see drawings as sensitive, but we do not consider them as sensitive automatically,” the CEO reportedly said. “When it comes to cameras in a public environment, for example, half the point is that they should be visible, therefore a drawing with camera placements in itself is not very sensitive.”

It remains unclear whether the stolen RDP credentials were a factor in this incident. But the password to the Gunnebo RDP account — “password01” — suggests the security of its IT systems may have been lacking in other areas as well.

After this author posted a request for contact from Gunnebo on Twitter, KrebsOnSecurity heard from Rasmus Jansson, an account manager at Gunnebo who specializes in protecting client systems from electromagnetic pulse (EMP) attacks or disruption, short bursts of energy that can damage electrical equipment.

Jansson said he relayed the stolen credentials to the company’s IT specialists, but that he does not know what actions the company took in response. Reached by phone today, Jansson said he quit the company in August, right around the time Gunnebo disclosed the thwarted ransomware attack. He declined to comment on the particulars of the extortion incident.

Ransomware attackers often spend weeks or months inside of a target’s network before attempting to deploy malware across the network that encrypts servers and desktop systems unless and until a ransom demand is met.

That’s because gaining the initial foothold is rarely the difficult part of the attack. In fact, many ransomware groups now have such an embarrassment of riches in this regard that they’ve taken to hiring external penetration testers to carry out the grunt work of escalating that initial foothold into complete control over the victim’s network and any data backup systems  — a process that can be hugely time consuming.

But prior to launching their ransomware, it has become common practice for these extortionists to offload as much sensitive and proprietary data as possible. In some cases, this allows the intruders to profit even if their malware somehow fails to do its job. In other instances, victims are asked to pay two extortion demands: One for a digital key to unlock encrypted systems, and another in exchange for a promise not to publish, auction or otherwise trade any stolen data. Continue reading →


12
Oct 20

Microsoft Uses Trademark Law to Disrupt Trickbot Botnet

Microsoft Corp. has executed a coordinated legal sneak attack in a bid to disrupt the malware-as-a-service botnet Trickbot, a global menace that has infected millions of computers and is used to spread ransomware. A court in Virginia granted Microsoft control over many Internet servers Trickbot uses to plunder infected systems, based on novel claims that the crime machine abused the software giant’s trademarks. However, it appears the operation has not completely disabled the botnet.

A spam email containing a Trickbot-infected attachment that was sent earlier this year. Image: Microsoft.

“We disrupted Trickbot through a court order we obtained as well as technical action we executed in partnership with telecommunications providers around the world,” wrote Tom Burt, corporate vice president of customer security and trust at Microsoft, in a blog post this morning about the legal maneuver. “We have now cut off key infrastructure so those operating Trickbot will no longer be able to initiate new infections or activate ransomware already dropped into computer systems.”

Microsoft’s action comes just days after the U.S. military’s Cyber Command carried out its own attack that sent all infected Trickbot systems a command telling them to disconnect themselves from the Internet servers the Trickbot overlords used to control them. The roughly 10-day operation by Cyber Command also stuffed millions of bogus records about new victims into the Trickbot database in a bid to confuse the botnet’s operators.

In legal filings, Microsoft argued that Trickbot irreparably harms the company “by damaging its reputation, brands, and customer goodwill. Defendants physically alter and corrupt Microsoft products such as the Microsoft Windows products. Once infected, altered and controlled by Trickbot, the Windows operating system ceases to operate normally and becomes tools for Defendants to conduct their theft.”

From the civil complaint Microsoft filed on October 6 with the U.S. District Court for the Eastern District of Virginia:

“However, they still bear the Microsoft and Windows trademarks. This is obviously meant to and does mislead Microsoft’s customers, and it causes extreme damage to Microsoft’s brands and trademarks.”

“Users subject to the negative effects of these malicious applications incorrectly believe that Microsoft and Windows are the source of their computing device problems. There is great risk that users may attribute this problem to Microsoft and associate these problems with Microsoft’s Windows products, thereby diluting and tarnishing the value of the Microsoft and Windows trademarks and brands.”

Microsoft said it will leverage the seized Trickbot servers to identify and assist Windows users impacted by the Trickbot malware in cleaning the malware off of their systems.

Trickbot has been used to steal passwords from millions of infected computers, and reportedly to hijack access to well more than 250 million email accounts from which new copies of the malware are sent to the victim’s contacts.

Trickbot’s malware-as-a-service feature has made it a reliable vehicle for deploying various strains of ransomware, locking up infected systems on a corporate network unless and until the company agrees to make an extortion payment.

A particularly destructive ransomware strain that is closely associated with Trickbot — known as “Ryuk” or “Conti” — has been responsible for costly attacks on countless organizations over the past year, including healthcare providers, medical research centers and hospitals.

One recent Ryuk victim is Universal Health Services (UHS), a Fortune 500 hospital and healthcare services provider that operates more than 400 facilities in the U.S. and U.K. Continue reading →


10
Oct 20

Report: U.S. Cyber Command Behind Trickbot Tricks

A week ago, KrebsOnSecurity broke the news that someone was attempting to disrupt the Trickbot botnet, a malware crime machine that has infected millions of computers and is often used to spread ransomware. A new report Friday says the coordinated attack was part of an operation carried out by the U.S. military’s Cyber Command.

Image: Shutterstock.

On October 2, KrebsOnSecurity reported that twice in the preceding ten days, an unknown entity that had inside access to the Trickbot botnet sent all infected systems a command telling them to disconnect themselves from the Internet servers the Trickbot overlords used to control compromised Microsoft Windows computers.

On top of that, someone had stuffed millions of bogus records about new victims into the Trickbot database — apparently to confuse or stymie the botnet’s operators.

In a story published Oct. 9, The Washington Post reported that four U.S. officials who spoke on condition of anonymity said the Trickbot disruption was the work of U.S. Cyber Command, a branch of the Department of Defense headed by the director of the National Security Agency (NSA).

The Post report suggested the action was a bid to prevent Trickbot from being used to somehow interfere with the upcoming presidential election, noting that Cyber Command was instrumental in disrupting the Internet access of Russian online troll farms during the 2018 midterm elections.

The Post said U.S. officials recognized their operation would not permanently dismantle Trickbot, describing it rather as “one way to distract them for at least a while as they seek to restore their operations.” Continue reading →


2
Oct 20

Attacks Aimed at Disrupting the Trickbot Botnet

Over the past 10 days, someone has been launching a series of coordinated attacks designed to disrupt Trickbot, an enormous collection of more than two million malware-infected Windows PCs that are constantly being harvested for financial data and are often used as the entry point for deploying ransomware within compromised organizations.

A text snippet from one of the bogus Trickbot configuration updates. Source: Intel 471

On Sept. 22, someone pushed out a new configuration file to Windows computers currently infected with Trickbot. The crooks running the Trickbot botnet typically use these config files to pass new instructions to their fleet of infected PCs, such as the Internet address where hacked systems should download new updates to the malware.

But the new configuration file pushed on Sept. 22 told all systems infected with Trickbot that their new malware control server had the address 127.0.0.1, which is a “localhost” address that is not reachable over the public Internet, according to an analysis by cyber intelligence firm Intel 471.

It’s not known how many Trickbot-infected systems received the phony update, but it seems clear this wasn’t just a mistake by Trickbot’s overlords. Intel 471 found that it happened yet again on Oct. 1, suggesting someone with access to the inner workings of the botnet was trying to disrupt its operations.

“Shortly after the bogus configs were pushed out, all Trickbot controllers stopped responding correctly to bot requests,” Intel 471 wrote in a note to its customers. “This possibly means central Trickbot controller infrastructure was disrupted. The close timing of both events suggested an intentional disruption of Trickbot botnet operations.”

Intel 471 CEO Mark Arena said it’s anyone’s guess at this point who is responsible.

“Obviously, someone is trying to attack Trickbot,” Arena said. “It could be someone in the security research community, a government, a disgruntled insider, or a rival cybercrime group. We just don’t know at this point.

Arena said it’s unclear how successful these bogus configuration file updates will be given that the Trickbot authors built a fail-safe recovery system into their malware. Specifically, Trickbot has a backup control mechanism: A domain name registered on EmerDNS, a decentralized domain name system.

“This domain should still be in control of the Trickbot operators and could potentially be used to recover bots,” Intel 471 wrote.

But whoever is screwing with the Trickbot purveyors appears to have adopted a multi-pronged approach: Around the same time as the second bogus configuration file update was pushed on Oct. 1, someone stuffed the control networks that the Trickbot operators use to keep track of data on infected systems with millions of new records.

Alex Holden is chief technology officer and founder of Hold Security, a Milwaukee-based cyber intelligence firm that helps recover stolen data. Holden said at the end of September Trickbot held passwords and financial data stolen from more than 2.7 million Windows PCs.

By October 1, Holden said, that number had magically grown to more than seven million.

“Someone is flooding the Trickbot system with fake data,” Holden said. “Whoever is doing this is generating records that include machine names indicating these are infected systems in a broad range of organizations, including the Department of Defense, U.S. Bank, JP Morgan Chase, PNC and Citigroup, to name a few.” Continue reading →