Operator of global secure messaging system for banks warns of “highly adaptive campaign”
Concerns that the massive $81 million cyber heist at the Bangladesh Bank recently was just a precursor of things to come in the banking industry appeared to be confirmed Friday with news that another bank has been similarly compromised.
Meanwhile, in a related development, security researchers at BAE Systems digging into the Bangladesh Bank breach released a report Friday claiming they had found evidence linking the heist to the devastating intrusion at Sony Pictures in 2014.
SWIFT, the Society for Worldwide Interbank Financial Telecommunication, the organization that runs the core financial messaging system used by more than 11,000 financial institutions globally, Friday confirmed a second instance in which attackers had managed to illegally transfer funds from a member bank by using the SWIFT system.
As with the Bangladesh Bank theft, the second incident was the result of the attackers managing to exploit vulnerabilities in the banks’ funds transfer initiation process — and not because of a security vulnerability in the SWIFT system itself, the banking organization said in a statement.
Security researchers believe the Bangladesh heist happened because the attackers were able to obtain valid credentials used by bank officials to log into the SWIFT system, and used that access to transfer funds. They then used malware to manipulate payment confirmations from the SWIFT system in an attempt to hide the transfers.
In the second instance too, the attackers were able to bypass security controls the bank had in place for initiating funds transfers over SWIFT. They also used malware to manipulate a PDF reader used by the bank to read payment confirmations in such a manner as to hide evidence of their illegal funds transfers, SWIFT said.
“Forensic experts believe this new discovery evidences that the malware used in the earlier reported customer incident was not a single occurrence, but part of a wider and highly adaptive campaign targeting banks,” the organization warned. The attacks suggest a “deep and sophisticated knowledge” of the operational controls in the targeted banks that may have been obtained from a malicious insider, theft or a combination of both, SWIFT said. As is its customary practice, SWIFT did not identify the second victim.
But BAE said its research showed a commercial bank in Vietnam had been targeted in a manner similar to Bangladesh Bank. While the malware used in the second attack was tailored for use against that specific Vietnam bank, the code-base was the same as the one used in the Bangladesh Bank incident.
The authors of the malware also used a unique and distinctive file erase function in both attacks for wiping files from disk.
BAE’s investigation of the code used in the function showed that it had also been previously used in the malware toolkit associated with the attacks on Sony, BAE said. The BAE report does not mention Sony by name but instead refers to it as a major entertainment company that suffered a breach in late 2014.
In addition to the file-delete functionality, there are other similarities in the malware code used in the Sony attacks and the recent bank attacks to suggest a link, BAE said. For instance, both code samples include the same typos and spelling errors.
The exclusive use of Visual C++ 6.0, a development environment dating back to 1998, in the Sony and bank code samples is another clue. “The use of such infrastructure for development is not unheard of, but it does leave a distinctive tool-mark with which to link the malware samples,” BAE said in its report.
Researchers from other security firms have previously traced the Sony attacks back to a group of North Korean threat actors believed responsible for a series of earlier attacks on government, military and commercial targets in the US, South Korea, Japan, China and Taiwan. The US government itself has formally accused North Korea of being behind the attacks on Sony.
BAE’s research suggesting a link between the Sony attack and the bank attacks raises fresh questions over attribution. If BAE is right, then it must mean either that North Korean threat actors are behind the bank attacks, or that previous assumptions about North Korea’s role in the Sony attacks were premature. Another possibility is that the same attack kit and malware used in the Sony attack is now being used by another group of threat actors.
Jai Vijayan is a seasoned technology reporter with over 20 years of experience in IT trade journalism. He was most recently a Senior Editor at Computerworld, where he covered information security and data privacy issues for the publication. Over the course of his 20-year … View Full Bio