Ransomware


8
Jul 19

Who’s Behind the GandCrab Ransomware?

The crooks behind an affiliate program that paid cybercriminals to install the destructive and wildly successful GandCrab ransomware strain announced on May 31, 2019 they were terminating the program after allegedly having earned more than $2 billion in extortion payouts from victims. What follows is a deep dive into who may be responsible for recruiting new members to help spread the contagion.

Image: Malwarebytes.

Like most ransomware strains, the GandCrab ransomware-as-a-service offering held files on infected systems hostage unless and until victims agreed to pay the demanded sum. But GandCrab far eclipsed the success of competing ransomware affiliate programs largely because its authors worked assiduously to update the malware so that it could evade antivirus and other security defenses.

In the 15-month span of the GandCrab affiliate enterprise beginning in January 2018, its curators shipped five major revisions to the code, each corresponding with sneaky new features and bug fixes aimed at thwarting the efforts of computer security firms to stymie the spread of the malware.

“In one year, people who worked with us have earned over US $2 billion,” read the farewell post by the eponymous GandCrab identity on the cybercrime forum Exploit[.]in, where the group recruited many of its distributors. “Our name became a generic term for ransomware in the underground. The average weekly income of the project was equal to US $2.5 million.”

The message continued:

“We ourselves have earned over US $150 million in one year. This money has been successfully cashed out and invested in various legal projects, both online and offline ones. It has been a pleasure to work with you. But, like we said, all things come to an end. We are getting a well-deserved retirement. We are a living proof that you can do evil and get off scot-free. We have proved that one can make a lifetime of money in one year. We have proved that you can become number one by general admission, not in your own conceit.”

Evil indeed, when one considers the damage inflicted on so many individuals and businesses hit by GandCrab — easily the most rapacious and predatory malware of 2018 and well into 2019.

The GandCrab identity on Exploit[.]in periodically posted updates about victim counts and ransom payouts. For example, in late July 2018, GandCrab crowed that a single affiliate of the ransomware rental service had infected 27,031 victims in the previous month alone, receiving about $125,000 in commissions.

The following month, GandCrab bragged that the program in July 2018 netted almost 425,000 victims and extorted more than one million dollars worth of cryptocurrencies, much of which went to affiliates who helped to spread the infections.

Russian security firm Kaspersky Lab estimated that by the time the program ceased operations, GandCrab accounted for up to half of the global ransomware market.

ONEIILK2

It remains unclear how many individuals were active in the core GandCrab malware development team. But KrebsOnSecurity located a number of clues that point to the real-life identity of a Russian man who appears to have been put in charge of recruiting new affiliates for the program.

In November 2018, a GandCrab affiliate posted a screenshot on the Exploit[.]in cybercrime forum of a private message between himself and a forum member known variously as “oneiilk2” and “oneillk2” that showed the latter was in charge of recruiting new members to the ransomware earnings program.

Oneiilk2 also was a successful GandCrab affiliate in his own right. In May 2018, he could be seen in multiple Exploit[.]in threads asking for urgent help obtaining access to hacked businesses in South Korea. These solicitations go on for several weeks that month — with Oneiilk2 saying he’s willing to pay top dollar for the requested resources. At the same time, Oneiilk2 can be seen on Exploit asking for help figuring out how to craft a convincing malware lure using the Korean alphabet.

Later in the month, Oneiilk2 says he no longer needs assistance on that request. Just a few weeks later, security firms began warning that attackers were staging a spam campaign to target South Korean businesses with version 4.3 of GandCrab. Continue reading →


3
Jun 19

Report: No ‘Eternal Blue’ Exploit Found in Baltimore City Ransomware

For almost the past month, key computer systems serving the government of Baltimore, Md. have been held hostage by a ransomware strain known as “Robbinhood.” Media publications have cited sources saying the Robbinhood version that hit Baltimore city computers was powered by “Eternal Blue,” a hacking tool developed by the U.S. National Security Agency (NSA) and leaked online in 2017. But new analysis suggests that while Eternal Blue could have been used to spread the infection, the Robbinhood malware itself contains no traces of it.

On May 25, The New York Times cited unnamed security experts briefed on the attack who blamed the ransomware’s spread on the Eternal Blue exploit, which was linked to the global WannaCry ransomware outbreak in May 2017.

That story prompted a denial from the NSA that Eternal Blue was somehow used in the Baltimore attack. It also moved Baltimore City Council President Brandon Scott to write the Maryland governor asking for federal disaster assistance and reimbursement as a result.

But according to Joe Stewart, a seasoned malware analyst now consulting with security firm Armor, the malicious software used in the Baltimore attack does not contain any Eternal Blue exploit code. Stewart said he obtained a sample of the malware that he was able to confirm was connected to the Baltimore incident.

“We took a look at it and found a pretty vanilla ransomware binary,” Stewart said. “It doesn’t even have any means of spreading across networks on its own.”

Stewart said while it’s still possible that the Eternal Blue exploit was somehow used to propagate the Robbinhood ransomware, it’s not terribly likely. Stewart said in a typical breach that leads to a ransomware outbreak, the intruders will attempt to leverage a single infection and use it as a jumping-off point to compromise critical systems on the breached network that would allow the malware to be installed on a large number of systems simultaneously.

“It certainly wouldn’t be the go-to exploit if your objective was to identify critical systems and then only when you’re ready launch the attack so you can do it all at once,” Stewart said. “At this point, Eternal Blue is probably going to be detected by internal [security] systems, or the target might already be patched for it.”

It is not known who is behind the Baltimore ransomware attack, but Armor said it was confident that the bad actor(s) in this case were the same individual(s) using the now-suspended twitter account @Robihkjn (Robbinhood). Until it was suspended at around 3:00 p.m. ET today (June 3), the @Robihkjn account had been taunting the mayor of Baltimore and city council members, who have refused to pay the ransom demand of 13 bitcoin — approximately $100,000.

In several of those tweets, the Twitter account could be seen posting links to documents allegedly stolen from Baltimore city government systems, ostensibly to both prove that those behind the Twitter account were responsible for the attack, and possibly to suggest what may happen to more of those documents if the city refuses to pay up by the payment deadline set by the extortionists — currently June 7, 2019 (the attackers postponed that deadline once already).

Some of @robihkjn’s tweets taunting Baltimore city leaders over non-payment of the $100,000 ransomware demand. The tweets included links to images of documents allegedly stolen by the intruders.

Over the past few days, however, the tweets from @Robinhkjn have grown more frequent and profanity-laced, directed at Baltimore’s leaders. The account also began tagging dozens of reporters and news organizations on Twitter.

Stewart said the @Robinhkjn Twitter account may be part of an ongoing campaign by the attackers to promote their own Robbinhood ransomware-as-a-service offering. According to Armor’s analysis, Robbinhood comes with multiple HTML templates that can be used to substitute different variables of the ransom demand, such as the ransom amount and the .onion address that victims can use to negotiate with the extortionists or pay a ransom demand. Continue reading →


2
Jan 19

Cloud Hosting Provider DataResolution.net Battling Christmas Eve Ransomware Attack

Cloud hosting provider Dataresolution.net is struggling to bring its systems back online after suffering a ransomware infestation on Christmas Eve, KrebsOnSecurity has learned. The company says its systems were hit by the Ryuk ransomware, the same malware strain that crippled printing and delivery operations for multiple major U.S. newspapers over the weekend.

San Juan Capistrano, Calif. based Data Resolution LLC serves some 30,000 businesses worldwide, offering software hosting, business continuity systems, cloud computing and data center services.

The company has not yet responded to requests for comment. But according to a status update shared by Data Resolution with affected customers on Dec. 29, 2018, the attackers broke in through a compromised login account on Christmas Eve and quickly began infecting servers with the Ryuk ransomware strain.

Part of an update on the outage shared with Data Resolution customers via Dropbox on Dec. 29, 2018.

The intrusion gave the attackers control of Data Resolution’s data center domain, briefly locking the company out of its own systems. The update sent to customers states that Data Resolution shut down its network to halt the spread of the infection and to work through the process of cleaning and restoring infected systems.

Data Resolution is assuring customers that there is no indication any data was stolen, and that the purpose of the attack was to extract payment from the company in exchange for a digital key that could be used to quickly unlock access to servers seized by the ransomware.

A snippet of an update that Data Resolution shared with affected customers on Dec. 31, 2018.

The Ryuk ransomware strain was first detailed in an August 2018 report by security firm CheckPoint, which says the malware may be tied to a sophisticated North Korean hacking team known as the Lazarus Group.

Ryuk reportedly was the same malware that infected the Los Angeles Times‘ Olympic printing plant over the weekend, an attack that led to the disruption of newspaper printing and delivery services for a number of publications that rely on the plant — including the Los Angeles Times and the San Diego Union Tribune.

A status update shared by Data Resolution with affected customers earlier today indicates the cloud hosting provider is still working to restore email access and multiple databases for clients. The update also said Data Resolution is in the process of restoring service for companies relying on it to host installations of Dynamics GP, a popular software package that many organizations use for accounting and payroll services.  Continue reading →