A harmful new malware loader with options for figuring out whether or not it is on a enterprise system or a private laptop has begun quickly infecting programs worldwide over the previous few months.
Researchers at VMware Carbon Black are monitoring the menace, dubbed BatLoader, and say its operators are utilizing the dropper to distribute quite a lot of malware instruments together with a banking Trojan, an info stealer, and the Cobalt Strike post-exploit toolkit on sufferer programs. The menace actor’s tactic has been to host the malware on compromised web sites and lure customers to these websites utilizing search engine marketing (web optimization) poisoning strategies.
Residing Off the Land
BatLoader depends closely on batch and PowerShell scripts to realize an preliminary foothold on a sufferer machine and to obtain different malware onto it. This has made the marketing campaign onerous to detect and block, particularly within the early levels, analysts from VMware Carbon Black’s managed detection and response (MDR) workforce mentioned in a report launched on Nov. 14.
VMware mentioned its Carbon Black MDR workforce had noticed 43 profitable infections within the final 90 days, along with quite a few different unsuccessful makes an attempt the place a sufferer downloaded the preliminary an infection file however didn’t execute it. 9 of the victims had been organizations within the enterprise companies sector, seven had been monetary companies firms, and 5 had been in manufacturing. Different victims included organizations within the training, retail, IT, and healthcare sectors.
On Nov. 9, eSentire mentioned its threat-hunting workforce had noticed BatLoader’s operator luring victims to web sites masquerading as obtain pages for well-liked enterprise software program reminiscent of LogMeIn, Zoom, TeamViewer, and AnyDesk. The menace actor distributed hyperlinks to those web sites by way of advertisements that confirmed up prominently in search engine outcomes when customers looked for any of those software program merchandise.
The safety vendor mentioned that in a single late October incident, an eSentire buyer arrived at a faux LogMeIn obtain web page and downloaded a Home windows installer that, amongst different issues, profiles the system and makes use of the data to retrieve a second-stage payload.
“What makes BatLoader attention-grabbing is that it has logic constructed into it that determines if the sufferer laptop is a private laptop or a company laptop,” says Keegan Keplinger, analysis and reporting lead with eSentire’s TRU analysis workforce. “It then drops the kind of malware acceptable for the state of affairs.”
Selective Payload Supply
For instance, if BatLoader hits a private laptop, it downloads Ursnif banking malware and the Vidar info stealer. If it hits a domain-joined or company laptop, it downloads Cobalt Strike and the Syncro distant monitoring and administration device, along with the banking Trojan and knowledge stealer.
“If BatLoader lands on a private laptop, it can proceed with fraud, infostealing, and banking-based payloads like Ursnif,” Keegan says. “If BatLoader detects that it is in an organizational setting, it can proceed with intrusion instruments like Cobalt Strike and Syncro.”
Keegan says eSentire has noticed “lots” of latest cyberattacks involving BatLoader. Many of the assaults are opportunistic and hit anybody searching for trusted and well-liked free software program instruments.
“To get in entrance of organizations, BatLoader leverages poisoned advertisements in order that when workers search for trusted free software program, like LogMeIn and Zoom, they as a substitute land on websites managed by attackers, delivering BatLoader.”
Overlaps With Conti, ZLoader
VMware Carbon Black mentioned that whereas there are a number of elements of the BatLoader marketing campaign which might be distinctive, there are additionally a number of attributes of the assault chain which have a resemblance with the Conti ransomware operation.
The overlaps embrace an IP deal with that the Conti group utilized in a marketing campaign leveraging the Log4j vulnerability, and using a distant administration device known as Atera that Conti has utilized in earlier operations.
Along with the similarities with Conti, BatLoader additionally has a number of overlaps with Zloader, a banking Trojan that seems derived from the Zeus banking Trojan of the early 2000s, the safety vendor mentioned. The most important similarities there embrace using web optimization poisoning to lure victims to malware-laden web sites, using Home windows Installer for establishing an preliminary foothold and using PowerShell, batch scripts, and different native OS binaries throughout the assault chain.
Mandiant was the primary to report on BatLoader. In a weblog submit in February, the safety vendor reported observing a menace actor utilizing “free productiveness apps set up” and “free software program growth instruments set up” themes as web optimization key phrases to lure customers to obtain websites.
“This preliminary BatLoader compromise was the start of a multi-stage an infection chain that gives the attackers with a foothold contained in the goal group,” Mandiant mentioned. The attackers used each stage to arrange the subsequent part of the assault chain utilizing instruments reminiscent of PowerShell, Msiexec.exe, and Mshta.exe to evade detection.
