Shamoon Attacks Possibly Aided by Greenbug Group

The stolen credentials used in the recent Shamoon attacks aimed at organizations in the Persian Gulf may have been supplied by a threat group tracked by Symantec as “Greenbug.”

Shamoon, aka Disttrack, is a disk-wiping malware that became widely known in 2012, when it damaged 35,000 computers belonging to petroleum and natural gas company Saudi Aramco. Shamoon 2, a more recent version of the threat, was recently used to target organizations in Saudi Arabia, including the country’s General Authority of Civil Aviation (GACA).

The first wave of Shamoon 2 attacks was launched on November 17 and a second wave on November 29. The attacks, which some have attributed to Iran, relied on the Disttrack malware to automatically start wiping infected systems at a specified time.

The malware was planted on targeted systems using stolen credentials, and security firm Symantec believes the information may have been obtained in a prior attack launched by a threat actor named Greenbug.

This cyber espionage group has used a remote access Trojan (RAT) called Ismdoor and various other tools in attacks aimed at organizations in the Middle East. The attackers targeted aviation, investment, government and education organizations in several countries, including Saudi Arabia, Iran, Iraq, Bahrain, Qatar, Kuwait and Turkey, and a Saudi company in Australia.

Greenbug has sent out fake business proposal emails to trick users into downloading malware onto their systems. The attackers delivered a RAR archive that stored a clean PDF and a compiled HTML help file (.chm) that contained the Ismdoor Trojan.

In order to avoid detection, the malware has been hidden in alternate data streams (ADS). Once executed, Ismdoor opens a backdoor and uses PowerShell for command and control (C&C) purposes. The Trojan is designed to install other pieces of malware, including ones capable of logging keystrokes and collecting browser, email and other sensitive data.

Symantec determined that Greenbug may have supplied credentials for the Shamoon attacks after detecting an Ismdoor infection on an administrator computer housed by one of the organizations targeted with Disttrack.

Researchers have not found any solid evidence linking the threat actors, but they pointed out that Ismdoor and other Greenbug tools became inactive just one day before the November 17 attacks.

Palo Alto Networks reported earlier this month that a variant of the Shamoon 2 malware is also designed to target virtualization products, likely in an effort to make recovery more difficult for attacked organizations.

Saudi Arabia has warned organizations to be on alert following a series of new attacks, Reuters reported on Monday. The country’s labor ministry, a chemicals firm and other companies have been allegedly hit.