The IMF has faced repeated cyber attacks in recent years. It routinely collects sensitive information about the financial conditions of its 187 member nations. Some data in its computer systems could conceivably be used to influence or trade currencies, bonds and other financial instruments in markets around the world.
The latest infiltration was sophisticated in that it involved significant reconnaissance prior to the attack, and code written specifically to penetrate the IMF, said Tom Kellermann, a former cybersecurity specialist at the World Bank who has been tracking the incident.
"This isn't malware you've seen before," he said, making it that much more difficult to detect. The concern, Mr. Kellermann said, is that hackers designed their attack to gain market-moving insider information.
The attackers appeared to have broad access to IMF systems, which would give them visibility into IMF plans, particularly as it relates to bailing out the economies of countries on shaky financial footing, Mr. Kellermann said.