“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,” Swift said in a statement. “The attackers clearly exhibit a deep and sophisticated knowledge of specific operational controls within the targeted banks –- knowledge that may have been gained from malicious insiders or cyber attacks, or a combination of both.”

In its warning, Swift said customers using PDF reader applications to check confirmation messages should take particular care. Hundreds of billions of dollars are moved internationally through the Swift system every day.

Investigators examining the theft from Bangladesh's central bank have uncovered evidence of three hacking groups — including a group linked to North Korea — inside the bank's network but say it was an unidentified group that pulled off the heist, people familiar with the bank's internal investigation said earlier this week. The attempted theft of almost $1 billion has prompted central banks around the globe to review defenses against hackers.

The theft investigation has turned into a massive global manhunt involving Interpol and the Federal Bureau of Investigation. The FBI suspects an insider with access to the Bangladesh bank's technology may have aided in the heist, according to the person briefed on the investigation.

“Malicious insiders or external attackers have managed to submit Swift messages from financial institutions' back offices, PCs or workstations connected to their local interface to the Swift network,” Swift said. “The modus operandi of the attackers is similar in both cases.”

Bloomberg

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