The new warnings center on three types of unrelated malicious code. For starters, malware has been spotted in the wild that is being used to drain cash from ATMs in Mexico, although security researchers warn that it could go global. The Shifu banking Trojan, meanwhile, has moved beyond Japan and is now being used to target customers of four U.K. banks. Finally, the notorious Neutrino crimeware has gotten an upgrade, allowing it to scrape POS device memory and steal payment-card data.
The newly spotted ATM cash-out malware has been dubbed “GreenDispenser,” by cybersecurity firm Proofpoint, which says that while it has only seen the malware used to “cash out” ATMs in Mexico, the malicious code could soon spread to other countries (see Authorities Detain Suspects in ATM Cash-Out).
“GreenDispenser provides an attacker [with] the ability to walk up to an infected ATM and drain its cash vault,” Proofpoint security researcher Thoufique Haq says in a blog post. “When installed, GreenDispenser may display an ‘out of service’ message on the ATM, but attackers who enter the correct PIN codes can then drain the ATM’s cash vault and erase GreenDispenser using a deep-delete process, leaving little if any trace of how the ATM was robbed.” A deep delete in this case means that the malware not only deletes itself, but also employs Microsoft’s sdelete to make it much more difficult for any malware-related bits and bytes to be recovered via later digital forensic analysis.
The malware resembles the PadPin – a.k.a. Tyupkin – ATM malware that first surfaced in March 2014, and which could be used to make an ATM dispense all of its money, in what’s known as a “jackpotting” or cash-out attack, Proofpoint says, adding that it believes that installing the malware requires physical access to an ATM (see Easy Access Fuels ATM Attacks).
Like PadPin, GreenDispenser is designed to interact with a set of standard programming interfaces, or APIs, that are built into most ATM host computers and components, known as XFS – which stands for “extensions for financial services” (see Hacking ATMs: No Malware Required).
This new generation of ATM malware includes a number of tricks designed to disguise the presence of the malware, as well as prevent unauthorized thieves from using it to drain ATMs. For starters, any ATM that gets infected with GreenDispenser displays an “out of order message.” Proofpoint says it has recovered samples of the malware that display a message either in grammatically challenged English – “We regret this ATM is temporary out of service” – or else in Spanish: Temporalmente fuera de servicio.
Based on Proofpoint’s GreenDispenser teardown, it found that the malware was coded to only run if the year was 2015, and the month was earlier than September, thus suggesting that this might have been a test run, or else designed to avoid detection. To cash out the ATM, meanwhile, an attacker must enter a preset PIN, scan a QR code displayed on screen, and then enter a second PIN, after which they can instruct the ATM to dispense all of its money, or tell the malware to delete itself.
“We suspect that the attacker has an application that can run on a mobile phone with functionality to scan the barcode and derive the second PIN – a two-factor authentication of sorts,” Proofpoint says. “This feature ensures that only an authorized individual has the ability to perform the heist.”
The banking malware known as Shifu – after the Japanese word for thief – has returned, and is no longer just targeting Japanese banks. In a Sept. 25 blog post, the French researcher who maintains the Malware Don’t Need Coffee blog, who goes by the name Kafeine, warns that in recent days, the malware has been spotted targeting four U.K. banks: Bank of Scotland, Halifax, Lloyds Bank and TSB. To date, it’s not clear how many banking customers’ systems may have been infected with the malware.
In August, IBM reported that it first saw Shifu being used for in-the-wild attacks, beginning at least in April. But Kafeine says that after cross-referencing his findings on Sept. 24 with security researchers at Fox-IT and Dell SecureWorks, they found that collectively they had been tracking Shifu since September 2014. “We were using a ‘non public’ name to talk about it,” Kafeine reports.
In the United Kingdom, Shifu is being spread via malvertising attacks, Kafeine says. To date, it’s not clear if these attacks are part of a campaign that has successfully served malicious advertising via multiple popular sites, including dating sites Plenty of Fish and Match.com.
Source: Cyber Security Intelligence