The risk actor often called Paper Werewolf has been noticed completely concentrating on Russian entities with a brand new implant referred to as PowerModul.
The exercise, which happened between July and December 2024, singled out organizations within the mass media, telecommunications, development, authorities entities, and vitality sectors, Kaspersky mentioned in a brand new report printed Thursday.
Paper Werewolf, also called GOFFEE, is assessed to have carried out no less than seven campaigns since 2022, based on BI.ZONE, with the assaults primarily aimed toward authorities, vitality, monetary, media, and different organizations.
Assault chains mounted by the risk actor have additionally been noticed incorporating a disruptive element, whereby the intrusions transcend distributing malware for espionage functions to additionally change passwords belonging to worker accounts.
The assaults themselves are initiated through phishing emails that include a macro-laced lure doc, which, upon opening and enabling macros, paves the way in which for the deployment of a PowerShell-based distant entry trojan often called PowerRAT.
The malware is designed to ship a next-stage payload, typically a customized model of the Mythic framework agent often called PowerTaskel and QwakMyAgent. One other software within the risk actor’s arsenal is a malicious IIS module referred to as Owowa, which is used for retrieving Microsoft Outlook credentials entered by customers on the net consumer.
The newest set of assaults documented by Kaspersky begins with a malicious RAR archive attachment containing an executable that masquerades as a PDF or a Phrase doc utilizing a double extension (i.e., *.pdf.exe or *.doc.exe). When the executable is launched, the decoy file is downloaded from a distant server and proven to the person, whereas the an infection proceeds to the subsequent stage within the background.
“The file itself is a Home windows system file (explorer.exe or xpsrchvw.exe), with a part of its code patched with a malicious shellcode,” it mentioned. “The shellcode is much like what we noticed in earlier assaults, however as well as accommodates an obfuscated Mythic agent, which instantly begins speaking with the command-and-control (C2) server.”
The alternate assault sequence is much more elaborate, utilizing a RAR archive embedding a Microsoft Workplace doc with a macro that acts as a dropper to deploy and launch PowerModul, a PowerShell script able to receiving and executing further PowerShell scripts from the C2 server.
The backdoor is alleged to have been used for the reason that begin of 2024, with the risk actors initially utilizing it to obtain and execute PowerTaskel on compromised hosts. Among the different payloads dropped by PowerModul are listed under –
- FlashFileGrabber, which is used to steal information from detachable media, equivalent to flash drives, and exfiltrate them to the C2 server
- FlashFileGrabberOffline, a variant of FlashFileGrabber that searches detachable media for information with particular extensions, and when discovered, copies them to the native disk inside the “%TEMPpercentCacheStoreconnect” folder
- USB Worm, which is able to infecting detachable media with a replica of PowerModul
PowerTaskel is functionally much like PowerModul in that it is also designed to run PowerShell scripts despatched by the C2 server. However as well as, it will probably ship details about the focused surroundings within the type of a “checkin” message, in addition to execute different instructions acquired from the C2 server as duties. It is also outfitted to escalate privileges utilizing the PsExec utility.
In no less than one occasion, PowerTaskel has been discovered to obtain a script with a FolderFileGrabber element that, in addition to replicating the options of FlashFileGrabber, contains the power to assemble information from distant methods through a hardcoded community path utilizing the SMB protocol.
“For the primary time, they employed Phrase paperwork with malicious VBA scripts for preliminary an infection,” Kaspersky mentioned. “Just lately, we’ve got noticed that GOFFEE is more and more abandoning the usage of PowerTaskel in favor of the binary Mythic agent throughout lateral motion.”
The event comes as BI.ZONE attributed one other risk group referred to as Sapphire Werewolf to a phishing marketing campaign that distributes an up to date model of the open-source Amethyst Stealer.
The stealer retrieves “credentials from Telegram and varied browsers, together with Chrome, Opera, Yandex, Courageous, Orbitum, Atom, Kometa, and Edge Chromium, in addition to FileZilla and SSH configuration information,” the Russian firm mentioned, including it will probably additionally seize paperwork, together with these saved on detachable media.
