The Shamoon 2.0 malware used recently in attacks aimed at the Middle East has a fully functional ransomware module that can encrypt files on the infected device, Kaspersky Lab said on Monday.
The security firm has published a report detailing Shamoon 2.0 and a new piece of malware, dubbed “StoneDrill,” that has been connected to both Shamoon and the Iran-linked threat actor Charming Kitten, aka NewsBeef and Newscaster.
One of the most interesting pieces of information shared by the company about Shamoon 2.0 is that, in addition to its well-known wiper functionality, it includes a ransomware module. The ransomware functionality is currently inactive, but experts believe it could be leveraged in future Shamoon attacks.
Once it infects a machine, Shamoon checks the system time to determine when to drop the main payload, which allows the attackers to either wipe or encrypt files and partitions.
“In the ‘encryption/ransomware’ mode, a weak pseudo – random RC4 key is generated, which is further encrypted by the RSA public key and stored directly on the hard drive (at ) starting at offset 0x201, right after the master boot record,” Kaspersky said in its report.
The ransomware module can be used to encrypt Shamoon components, files stored in Windows folders (e.g. Desktop, Downloads, Documents, Pictures), NTFS master file table (MFT) data from all drives except the system drive, files in Windows system folders, and part of the FirmwareBootDevice partition.
Shamoon is not the only wiper whose authors have recently decided to add ransomware functionality to their creation. Late last year, researchers reported that a variant of the KillDisk malware, which had been involved in the attacks on Ukraine’s energy sector, had been designed to encrypt files and hold them for ransom instead of deleting them.
Kaspersky Lab also revealed that the resources used by Shamoon appear to have a Yemeni Arabic language ID. While this could indicate that the threat group behind Shamoon is located in Yemen, which would also have a good reason to target Saudi Arabia, it’s also possible that this is a false flag. Previously, researchers attributed the Shamoon attacks to Iran.
Related: Shamoon Malware Delivered via Weaponized Documents