Joker’s Stash Carding Market to Call it Quits

January 18, 2021
37 Comments

Joker’s Stash, by some accounts the largest underground shop for selling stolen credit card and identity data, says it’s closing up shop effective mid-February 2021. The announcement came on the heels of a turbulent year for the major cybercrime store, and just weeks after U.S. and European authorities seized a number of its servers.

A farewell message posted by Joker’s Stash admin on Jan. 15, 2021.

The Russian and English language carding store first opened in October 2014, and quickly became a major source of “dumps” — information stolen from compromised payment cards that thieves can buy and use to create physical counterfeit copies of the cards.

But 2020 turned out to be a tough year for Joker’s Stash. As cyber intelligence firm Intel 471 notes, the curator of the store announced in October that he’d contracted COVID-19, spending a week in the hospital. Around that time, Intel 471 says many of Joker’s loyal customers started complaining that the shop’s payment card data quality was increasingly poor.

“The condition impacted the site’s forums, inventory replenishments and other operations,” Intel 471 said.

Image: Gemini Advisory

That COVID diagnosis may have affected the shop owner’s ability to maintain fresh and valid inventory on his site. Gemini Advisory, a New York City-based company that monitors underground carding shops, tracked a “severe decline” in the volume of compromised payment card accounts for sale on Joker’s Stash over the past six months.

“Joker’s Stash has received numerous user complaints alleging that card data validity is low, which even prompted the administrator to upload proof of validity through a card-testing service,” Gemini wrote in a blog post about the planned shutdown.

Image: Gemini Advisory

Then on Dec. 16, 2020, several of Joker’s long-held domains began displaying notices that the sites had been seized by the U.S. Department of Justice and Interpol. The crime shop quickly recovered, moving to new infrastructure and assuring the underground community that it would continue to operate normally.

Gemini estimates that Joker’s Stash generated more than a billion dollars in revenue over the past several years. Much of that revenue came from high-profile breaches, including tens of millions of payment card records stolen from major merchants including Saks Fifth Avenue, Lord and Taylor, Bebe Stores, Hilton Hotels, Jason’s Deli, Whole Foods, Chipotle, Wawa, Sonic Drive-In, the Hy-Vee supermarket chain, Buca Di Beppo, and Dickey’s BBQ.

Joker’s Stash routinely teased big breaches days or weeks in advance of selling payment card records stolen from those companies, and periodically linked to this site and other media outlets as proof of his shop’s prowess and authenticity.

Like many other top cybercrime bazaars, Joker’s Stash was a frequent target of phishers looking to rip off unwary or unsophisticated thieves. In 2018, KrebsOnSecurity detailed a vast network of fake Joker’s Stash sites set up to steal login credentials and bitcoin. The phony sites all traced back to the owners of a Pakistani web site design firm. Many of those fake sites are still active (e.g. jokersstash[.]su). Continue reading →

Microsoft Patch Tuesday, January 2021 Edition

January 12, 2021
36 Comments

Microsoft today released updates to plug more than 80 security holes in its Windows operating systems and other software, including one that is actively being exploited and another which was disclosed prior to today. Ten of the flaws earned Microsoft’s most-dire “critical” rating, meaning they could be exploited by malware or miscreants to seize remote control over unpatched systems with little or no interaction from Windows users.

Most concerning of this month’s batch is probably a critical bug (CVE-2021-1647) in Microsoft’s default anti-malware suite — Windows Defender — that is seeing active exploitation. Microsoft recently stopped providing a great deal of detail in their vulnerability advisories, so it’s not entirely clear how this is being exploited.

But Kevin Breen, director of research at Immersive Labs, says depending on the vector the flaw could be trivial to exploit.

“It could be as simple as sending a file,” he said. “The user doesn’t need to interact with anything, as Defender will access it as soon as it is placed on the system.”

Fortunately, this bug is probably already patched by Microsoft on end-user systems, as the company continuously updates Defender outside of the normal monthly patch cycle.

Breen called attention to another critical vulnerability this month — CVE-2020-1660 — which is a remote code execution flaw in nearly every version of Windows that earned a CVSS score of 8.8 (10 is the most dangerous).

“They classify this vulnerability as ‘low’ in complexity, meaning an attack could be easy to reproduce,” Breen said. “However, they also note that it’s ‘less likely’ to be exploited, which seems counterintuitive. Without full context of this vulnerability, we have to rely on Microsoft to make the decision for us.” Continue reading →

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SolarWinds: What Hit Us Could Hit Others

January 12, 2021
36 Comments

New research into the malware that set the stage for the megabreach at IT vendor SolarWinds shows the perpetrators spent months inside the company’s software development labs honing their attack before inserting malicious code into updates that SolarWinds then shipped to thousands of customers. More worrisome, the research suggests the insidious methods used by the intruders to subvert the company’s software development pipeline could be repurposed against many other major software providers.

In a blog post published Jan. 11, SolarWinds said the attackers first compromised its development environment on Sept. 4, 2019. Soon after, the attackers began testing code designed to surreptitiously inject backdoors into Orion, a suite of tools used by many Fortune 500 firms and a broad swath of the federal government to manage their internal networks.

Image: SolarWinds.

According to SolarWinds and a technical analysis from CrowdStrike, the intruders were trying to work out whether their “Sunspot” malware — designed specifically for use in undermining SolarWinds’ software development process — could successfully insert their malicious “Sunburst” backdoor into Orion products without tripping any alarms or alerting Orion developers.

In October 2019, SolarWinds pushed an update to their Orion customers that contained the modified test code. By February 2020, the intruders had used Sunspot to inject the Sunburst backdoor into the Orion source code, which was then digitally signed by the company and propagated to customers via SolarWinds’ software update process.

Crowdstrike said Sunspot was written to be able to detect when it was installed on a SolarWinds developer system, and to lie in wait until specific Orion source code files were accessed by developers. This allowed the intruders to “replace source code files during the build process, before compilation,” Crowdstrike wrote.

The attackers also included safeguards to prevent the backdoor code lines from appearing in Orion software build logs, and checks to ensure that such tampering wouldn’t cause build errors.

“The design of SUNSPOT suggests [the malware] developers invested a lot of effort to ensure the code was properly inserted and remained undetected, and prioritized operational security to avoid revealing their presence in the build environment to SolarWinds developers,” CrowdStrike wrote.

A third malware strain — dubbed “Teardrop” by FireEye, the company that first disclosed the SolarWinds attack in December — was installed via the backdoored Orion updates on networks that the SolarWinds attackers wanted to plunder more deeply.

So far, the Teardrop malware has been found on several government networks, including the Commerce, Energy and Treasury departments, the Department of Justice and the Administrative Office of the U.S. Courts.

SolarWinds emphasized that while the Sunspot code was specifically designed to compromise the integrity of its software development process, that same process is likely common across the software industry.

“Our concern is that right now similar processes may exist in software development environments at other companies throughout the world,” said SolarWinds CEO Sudhakar Ramakrishna. “The severity and complexity of this attack has taught us that more effectively combatting similar attacks in the future will require an industry-wide approach as well as public-private partnerships that leverage the skills, insight, knowledge, and resources of all constituents.”

Ubiquiti: Change Your Password, Enable 2FA

January 11, 2021
45 Comments

Ubiquiti, a major vendor of cloud-enabled Internet of Things (IoT) devices such as routers, network video recorders, security cameras and access control systems, is urging customers to change their passwords and enable multi-factor authentication. The company says an incident at a third-party cloud provider may have exposed customer account information and credentials used to remotely manage Ubiquiti gear.

In an email sent to customers today, Ubiquiti Inc. [NYSE: UI] said it recently became aware of “unauthorized access to certain of our information technology systems hosted by a third party cloud provider,” although it declined to name that provider.

The statement continues:

“We are not currently aware of evidence of access to any databases that host user data, but we cannot be certain that user data has not been exposed. This data may include your name, email address, and the one-way encrypted password to your account (in technical terms, the passwords are hashed and salted). The data may also include your address and phone number if you have provided that to us.”

Ubiquiti has not yet responded to requests for more information, but the notice was confirmed as official in a post on the company’s user support forum.

The warning from Ubiquiti carries particular significance because the company has made it fairly difficult for customers using the latest Ubiquiti firmware to interact with their devices without first authenticating through the company’s cloud-based systems. Continue reading →

Sealed U.S. Court Records Exposed in SolarWinds Breach

January 7, 2021
61 Comments

The ongoing breach affecting thousands of organizations that relied on backdoored products by network software firm SolarWinds may have jeopardized the privacy of countless sealed court documents on file with the U.S. federal court system, according to a memo released Wednesday by the Administrative Office (AO) of the U.S. Courts.

The judicial branch agency said it will be deploying more stringent controls for receiving and storing sensitive documents filed with the federal courts, following a discovery that its own systems were compromised as part of the SolarWinds supply chain attack. That intrusion involved malicious code being surreptitiously inserted into updates shipped by SolarWinds for some 18,000 users of its Orion network management software as far back as March 2020.

“The AO is working with the Department of Homeland Security on a security audit relating to vulnerabilities in the Judiciary’s Case Management/Electronic Case Files system (CM/ECF) that greatly risk compromising highly sensitive non-public documents stored on CM/ECF, particularly sealed filings,” the agency said in a statement published Jan. 6.

“An apparent compromise of the confidentiality of the CM/ECF system due to these discovered vulnerabilities currently is under investigation,” the statement continues. “Due to the nature of the attacks, the review of this matter and its impact is ongoing.”

The AO declined to comment on specific questions about their breach disclosure. But a source close to the investigation told KrebsOnSecurity that the federal court document system was “hit hard,” by the SolarWinds attackers, which multiple U.S. intelligence and law enforcement agencies have attributed as “likely Russian in origin.”

The source said the intruders behind the SolarWinds compromise seeded the AO’s network with a second stage “Teardrop” malware that went beyond the “Sunburst” malicious software update that was opportunistically pushed out to all 18,000 customers using the compromised Orion software. This suggests the attackers were targeting the agency for deeper access to its networks and communications.

The AO’s court document system powers a publicly searchable database called PACER, and the vast majority of the files in PACER are not restricted and are available to anyone willing to pay for the records.

But experts say many other documents stored in the AO’s system are sealed — either temporarily or indefinitely by the courts or parties to a legal matter — and may contain highly sensitive information, including intellectual property and trade secrets, or even the identities of confidential informants.

Nicholas Weaver, a lecturer at the computer science department at University of California, Berkeley, said the court document system doesn’t hold documents that are classified for national security reasons. But he said the system is full of sensitive sealed filings — such as subpoenas for email records and so-called “trap and trace” requests that law enforcement officials use to determine with whom a suspect is communicating via phone, when and for how long.

“This would be a treasure trove for the Russians knowing about a lot of ongoing criminal investigations,” Weaver said. “If the FBI has indicted someone but hasn’t arrested them yet, that’s all under seal. A lot of the investigative tools that get protected under seal are filed very early on in the process, often with gag orders that prevent [the subpoenaed party] from disclosing the request.”

The acknowledgement from the AO comes hours after the U.S. Justice Department said it also was a victim of the SolarWinds intruders, who took control over the department’s Office 365 system and accessed email sent or received from about three percent of DOJ accounts (the department has more than 100,000 employees). Continue reading →

All Aboard the Pequod!

January 7, 2021
206 Comments

Like countless others, I frittered away the better part of Jan. 6 doomscrolling and watching television coverage of the horrifying events unfolding in our nation’s capital, where a mob of President Trump supporters and QAnon conspiracy theorists was incited to lay siege to the U.S. Capitol. For those trying to draw meaning from the experience, might I suggest consulting the literary classic Moby Dick, which simultaneously holds clues about QAnon’s origins and offers an apt allegory about a modern-day Captain Ahab and his ill-fated obsessions.

Many have speculated that Jim Watkins, the administrator of the online message board 8chan (a.k.a. 8kun), and/or his son Ron are in fact “Q,” the anonymous persona behind the QAnon conspiracy theory, which holds that President Trump is secretly working to save the world from a satanic cult of pedophiles and cannibals.

Last year, as I was scrutinizing the computer networks that kept QAnon online, researcher Ron Guilmette pointed out a tantalizing utterance from Watkins the younger which adds tenuous credence to the notion that one or both of them is Q.

We’ll get to how the Great White Whale (the Capitol?) fits into this tale in a moment. But first, a bit of background. A person identified only as “Q” has for years built an impressive following for the far-right conspiracy movement by leaving periodic “Q drops,” cryptic messages that QAnon adherents spend much time and effort trying to decipher and relate to current events.

Researchers who have studied more than 5,000 Q drops are convinced that there are two distinct authors of these coded utterances. The leading theory is that those identities corresponded to the aforementioned father-and-son team responsible for operating 8chan.

Jim Watkins, 56, is the current owner of 8chan, a community perhaps now best known as a forum for violent extremists and mass shooters. Watkins is an American pig farmer based in the Philippines; Ron reportedly resides in Japan.

In the aftermath of back-to-back mass shootings on Aug. 3 and Aug. 4, 2019 in which a manifesto justifying one of the attacks was uploaded to 8chan, Cloudflare stopped providing their content delivery network to 8chan. Several other providers quickly followed suit, leaving 8chan offline for months before it found a haven at a notorious bulletproof hosting facility in Russia.

One reason Q watchers believe Ron and Jim Watkins may share authorship over the Q drops is that while 8chan was offline, the messages from Q ceased. The drops reappeared only months later when 8chan rebranded as 8kun.

CALL ME ISHMAEL

Here’s where the admittedly “Qonspiratorial” clue about the Watkins’ connection to Q comes in. On Aug. 5, 2019, Ron Watkins posted a Twitter message about 8chan’s ostracization which compared the community’s fate to that of the Pequod, the name of the doomed whaling ship in the Herman Melville classic “Moby Dick.”

“If we are still down in a few hours then maybe 8chan will just go clearnet and we can brave DDOS attacks like Ishmael on the Pequod,” Watkins the younger wrote.

Ishmael, the first-person narrator in the novel, is a somewhat disaffected American sailor who decides to try his hand at a whaling ship. Ishmael is a bit of a minor character in the book; very soon into the novel we are introduced to a much more interesting and enigmatic figure — a Polynesian harpooner by the name of Queequeg.

Apart from being a cannibal from the Pacific islands who has devoured many people, Queequeg is a pretty nice guy and shows Ismael the ropes of whaling life. Queequeg is covered head to toe in tattoos, which are described by the narrator as the work of a departed prophet and seer from the cannibal’s home island.

Like so many Q drops, Queequeg’s tattoos tell a mysterious tale, but we never quite learn what that full story is. Indeed, the artist who etched them into Queequeg’s body is long dead, and the cannibal himself can’t seem to explain what it all means.

Ishmael describes Queequeg’s mysterious markings in this passage:

“…a complete theory of the heavens and earth, and a mystical treatise on the art of attaining truth; so that Queequeg in his own proper person was a riddle to unfold; a wondrous work in one volume; but whose mysteries not even himself could read, though his own live heart beat against them; and these mysteries were therefore destined in the end to moulder away with the living parchment whereon they were inscribed, and so be unsolved to the last.” Continue reading →

Hamas May Be Threat to 8chan, QAnon Online

January 5, 2021
90 Comments

In October 2020, KrebsOnSecurity looked at how a web of sites connected to conspiracy theory movements QAnon and 8chan were being kept online by DDoS-Guard, a dodgy Russian firm that also hosts the official site for the terrorist group Hamas. New research shows DDoS-Guard relies on data centers provided by a U.S.-based publicly traded company, which experts say could be exposed to civil and criminal liabilities as a result of DDoS-Guard’s business with Hamas.

Many of the IP address ranges in in this map of QAnon and 8Chan-related sites — are assigned to VanwaTech. Source: twitter.com/Redrum_of_Crows

Last year’s story examined how a phone call to Oregon-based CNServers was all it took to briefly sideline multiple websites related to 8chan/8kun — a controversial online image board linked to several mass shootings — and QAnon, the far-right conspiracy theory which holds that a cabal of Satanic pedophiles is running a global child sex-trafficking ring and plotting against President Donald Trump.

From that piece:

A large number of 8kun and QAnon-related sites (see map above) are connected to the Web via a single Internet provider in Vancouver, Wash. called VanwaTech (a.k.a. “OrcaTech“). Previous appeals to VanwaTech to disconnect these sites have fallen on deaf ears, as the company’s owner Nick Lim reportedly has been working with 8kun’s administrators to keep the sites online in the name of protecting free speech.

After that story, CNServers and a U.K.-based hosting firm called SpartanHost both cut ties with VanwaTech. Following a brief disconnection, the sites came back online with the help of DDoS-Guard, an Internet company based in Russia. DDoS-Guard is now VanwaTech’s sole connection to the larger Internet.

A review of the several thousand websites hosted by DDoS-Guard is revelatory, as it includes a vast number of phishing sites and domains tied to cybercrime services or forums online.

Replying to requests for comment from a CBSNews reporter following up on my Oct. 2020 story, DDoS-Guard issued a statement saying, “We observe network neutrality and are convinced that any activity not prohibited by law in our country has the right to exist.”

But experts say DDoS-Guard’s business arrangement with a Denver-based publicly traded data center firm could create legal headaches for the latter thanks to the Russian company’s support of Hamas.

In a press release issued in late 2019, DDoS-Guard said its services rely in part on a traffic-scrubbing facility in Los Angeles owned by CoreSite [NYSE:COR], a real estate investment trust which invests in “carrier-neutral data centers and provides colocation and peering services.”

This facilities map published by DDoS-Guard suggests the company’s network actually has at least two points of presence in the United States.

Hamas has long been named by the U.S. Treasury and State departments as a Specially Designated Global Terrorist (SDGT) organization. Under such a designation, any U.S. person or organization that provides money, goods or services to an SDGT entity could face civil and/or criminal prosecution and hefty fines ranging from $250,000 to $1 million per violation. Continue reading →

Happy 11th Birthday, KrebsOnSecurity!

December 29, 2020
68 Comments

Today marks the 11th anniversary of KrebsOnSecurity! Thank you, Dear Readers, for your continued encouragement and support!

With the ongoing disruption to life and livelihood wrought by the Covid-19 pandemic, 2020 has been a fairly horrid year by most accounts. And it’s perhaps fitting that this was also a leap year, piling on an extra day to a solar rotation that most of us probably can’t wait to see in the rearview mirror.

But it was hardly a dull one for computer security news junkies. In almost every category — from epic breaches and ransomware to cybercrime justice and increasingly aggressive phishing and social engineering scams — 2020 was a year that truly went to eleven.

Almost 150 stories here this past year generated nearly 9,000 responses from readers (although about 6 percent of those were on just one story). Thank you all for your thoughtful engagement, wisdom, news tips and support.

I’d like to reprise a note from last year’s anniversary post concerning ads. A good chunk of the loyal readers here are understandably security- and privacy-conscious, and many block advertisements by default — including the ads displayed here.

KrebsOnSecurity does not run third-party ads and has no plans to change that; all of the creatives you see on this site are hosted in-house, are purely image-based, and are vetted first by Yours Truly. Love them or hate ’em, these ads help keep the content at KrebsOnSecurity free to any and all readers. If you’re currently blocking ads here, please consider making an exception for this site.

In case you missed them, some of the most popular feature/enterprise stories on the site this year (in no particular order) included:

The Joys of Owning an ‘OG’ Email Account
Confessions of an ID Theft Kingpin (Part II)
Why and Where You Should Plant Your Flag
Thinking of a Career in Cybersecurity? Read This
Turn on MFA Before Crooks Do it for You
Romanian Skimmer Gang in Mexico Outed by KrebsOnSecurity Stole $1.2 Billion
Who’s Behind the ‘Web Listings’ Mail Scam?
When in Doubt: Hang Up, Look Up, & Call Back
Riding the State Unemployment Fraud Wave
Would You Have Fallen for this Phone Scam?

VMware Flaw a Vector in SolarWinds Breach?

December 18, 2020
142 Comments

U.S. government cybersecurity agencies warned this week that the attackers behind the widespread hacking spree stemming from the compromise at network software firm SolarWinds used weaknesses in other, non-SolarWinds products to attack high-value targets. According to sources, among those was a flaw in software virtualization platform VMware, which the U.S. National Security Agency (NSA) warned on Dec. 7 was being used by Russian hackers to impersonate authorized users on victim networks.

On Dec. 7, 2020, the NSA said “Russian state-sponsored malicious cyber actors are exploiting a vulnerability in VMware Access and VMware Identity Manager products, allowing the actors access to protected data and abusing federated authentication.”

VMware released a software update to plug the security hole (CVE-2020-4006) on Dec. 3, and said it learned about the flaw from the NSA.

The NSA advisory (PDF) came less than 24 hours before cyber incident response firm FireEye said it discovered attackers had broken into its networks and stolen more than 300 proprietary software tools the company developed to help customers secure their networks.

On Dec. 13, FireEye disclosed that the incident was the result of the SolarWinds compromise, which involved malicious code being surreptitiously inserted into updates shipped by SolarWinds for users of its Orion network management software as far back as March 2020.

In its advisory on the VMware vulnerability, the NSA urged patching it “as soon as possible,” specifically encouraging the National Security System, Department of Defense, and defense contractors to make doing so a high priority.

The NSA said that in order to exploit this particular flaw, hackers would already need to have access to a vulnerable VMware device’s management interface — i.e., they would need to be on the target’s internal network (provided the vulnerable VMware interface was not accessible from the Internet). However, the SolarWinds compromise would have provided that internal access nicely.

In response to questions from KrebsOnSecurity, VMware said it has “received no notification or indication that the CVE 2020-4006 was used in conjunction with the SolarWinds supply chain compromise.”

VMware added that while some of its own networks used the vulnerable SolarWinds Orion software, an investigation has so far revealed no evidence of exploitation.

“While we have identified limited instances of the vulnerable SolarWinds Orion software in our environment, our own internal investigation has not revealed any indication of exploitation,” the company said in a statement. “This has also been confirmed by SolarWinds own investigations to date.”

On Dec. 17, DHS’s Cybersecurity and Infrastructure Security Agency (CISA) released a sobering alert on the SolarWinds attack, noting that CISA had evidence of additional access vectors other than the SolarWinds Orion platform.

CISA’s advisory specifically noted that “one of the principal ways the adversary is accomplishing this objective is by compromising the Security Assertion Markup Language (SAML) signing certificate using their escalated Active Directory privileges. Once this is accomplished, the adversary creates unauthorized but valid tokens and presents them to services that trust SAML tokens from the environment. These tokens can then be used to access resources in hosted environments, such as email, for data exfiltration via authorized application programming interfaces (APIs).”

Indeed, the NSA’s Dec. 7 advisory said the hacking activity it saw involving the VMware vulnerability “led to the installation of a web shell and follow-on malicious activity where credentials in the form of SAML authentication assertions were generated and sent to Microsoft Active Directory Federation Services (ADFS), which in turn granted the actors access to protected data.”

Also on Dec. 17, the NSA released a far more detailed advisory explaining how it has seen the VMware vulnerability being used to forge SAML tokens, this time specifically referencing the SolarWinds compromise.

Asked about the potential connection, the NSA said only that “if malicious cyber actors gain initial access to networks through the SolarWinds compromise, the TTPs [tactics, techniques and procedures] noted in our December 17 advisory may be used to forge credentials and maintain persistent access.”

“Our guidance in this advisory helps detect and mitigate against this, no matter the initial access method,” the NSA said.

Continue reading →

Malicious Domain in SolarWinds Hack Turned into ‘Killswitch’

December 16, 2020
88 Comments

A key malicious domain name used to control potentially thousands of computer systems compromised via the months-long breach at network monitoring software vendor SolarWinds was commandeered by security experts and used as a “killswitch” designed to turn the sprawling cybercrime operation against itself, KrebsOnSecurity has learned.

Austin, Texas-based SolarWinds disclosed this week that a compromise of its software update servers earlier this year may have resulted in malicious code being pushed to nearly 18,000 customers of its Orion platform. Many U.S. federal agencies and Fortune 500 firms use(d) Orion to monitor the health of their IT networks.

On Dec. 13, cyber incident response firm FireEye published a detailed writeup on the malware infrastructure used in the SolarWinds compromise, presenting evidence that the Orion software was first compromised back in March 2020. FireEye said hacked networks were seen communicating with a malicious domain name — avsvmcloud[.]com — one of several domains the attackers had set up to control affected systems.

As first reported here on Tuesday, there were signs over the past few days that control over the domain had been transferred to Microsoft. Asked about the changeover, Microsoft referred questions to FireEye and to GoDaddy, the current domain name registrar for the malicious site.

Today, FireEye responded that the domain seizure was part of a collaborative effort to prevent networks that may have been affected by the compromised SolarWinds software update from communicating with the attackers. What’s more, the company said the domain was reconfigured to act as a “killswitch” that would prevent the malware from continuing to operate in some circumstances.

“SUNBURST is the malware that was distributed through SolarWinds software,” FireEye said in a statement shared with KrebsOnSecurity. “As part of FireEye’s analysis of SUNBURST, we identified a killswitch that would prevent SUNBURST from continuing to operate.”

The statement continues:

“Depending on the IP address returned when the malware resolves avsvmcloud[.]com, under certain conditions, the malware would terminate itself and prevent further execution. FireEye collaborated with GoDaddy and Microsoft to deactivate SUNBURST infections.”

“This killswitch will affect new and previous SUNBURST infections by disabling SUNBURST deployments that are still beaconing to avsvmcloud[.]com. However, in the intrusions FireEye has seen, this actor moved quickly to establish additional persistent mechanisms to access to victim networks beyond the SUNBURST backdoor.

This killswitch will not remove the actor from victim networks where they have established other backdoors. However, it will make it more difficult to for the actor to leverage the previously distributed versions of SUNBURST.”

It is likely that given their visibility into and control over the malicious domain, Microsoft, FireEye, GoDaddy and others now have a decent idea which companies may still be struggling with SUNBURST infections.

The killswitch revelations came as security researchers said they’d made progress in decoding SUNBURST’s obfuscated communications methods. Chinese cybersecurity firm RedDrip Team published their findings on Github, saying its decoder tool had identified nearly a hundred suspected victims of the SolarWinds/Orion breach, including universities, governments and high tech companies.

Meanwhile, the potential legal fallout for SolarWinds in the wake of this breach continues to worsen. The Washington Post reported Tuesday that top investors in SolarWinds sold millions of dollars in stock in the days before the intrusion was revealed. SolarWinds’s stock price has fallen more than 20 percent in the past few days. The Post cited former enforcement officials at the U.S. Securities and Exchange Commission (SEC) saying the sales were likely to prompt an insider trading investigation.