A newly discovered attack sheds some light on how cyber espionage isn't just for nation-state interests but can also be used for possibly competitive or other spying purposes.
Researchers at Moscow-based Kaspersky have discovered and analyzed a cyberattack campaign they dubbed MontysThree that pitted what they believe is a Russian-speaking actor targeting the industrial sector within the country, stealing documents and files from specific targets. "For us, it looks like some kind of local story," says Denis Legezo, senior security researcher with Kaspersky's Global Research and Analysis Team. "I don't think they have some political agenda. It looks more like industrial espionage."
The global industrial sector has experienced its share of malware infections, both targeted and untargeted for several years. Attacks on operational technology networks have increased, and according to a new survey by industrial security firm Claroty, some 56% of industrial sector organizations worldwide have experienced more cyber threats during the COVID-19 pandemic.
MontysThree, which appears to have no connection to any threat groups Kaspersky currently tracks, uses some relatively unusual techniques in its attack campaign including steganography, a sophisticated method of masking malware behind images, as well as a relatively clunky method of remote access communications, running HTTP over the Remote Desktop Protocol (RDP). The group also planted a false flag in the code of some of its email files to appear as a Chinese-speaking actor, but Legezo says he was able to pull Cyrillic characters from the code that indicates that the author is actually a native Russian-speaker.
Legezo says the attackers posed as a local medical lab in a spear-phishing attack to get them to open rigged attachments. It has no pure cybercrime nexus, either, he says: "They didn't register any crypotolockers" or other signs of cybercrime, he says. "They are only data-gathering."
Kaspersky did not provide specifics on the targeted victims.
The loader malware — disguised with steganography — in the phishing email uses a bitmap file to hide the malware. The lures are RAR SFX files that include employee contact names, documentation, and medical results.
Steganography is an old but rarely used obfuscation method, and it's not easy to deploy. Legezo says he believes the attackers were trying to sneak past IDS/IPS tools in the victim networks by hiding the malware behind seemingly innocent image files.
MontysThree encrypts the payload and searches mainly for Microsoft and Adobe Acrobat files, while also conducting the usual espionage tasks of gathering intel of the target machines settings and characteristics. The attackers store their stolen files on public cloud services that include Google, Microsoft, and Dropbox, to camouflage their activity and avoid raising any alarms on security tools.
"They are mostly hunting for current information and documents," he says.
MontysThree also use an interesting method of remote access communications in lieu of embedding communications protocols in the malware. "Over RDP, they connect to a remote host and open Internet Explorer" and use the Control keyboard commands to select, copy, and paste stolen information. "It's the first time I've seen such a method of communication. It's quite naive," he says.
The attackers also use Citrix clients: "The Citrix communication is done using a similar procedure: The malware doesn't implement the protocol but rather searches for Windows Quick Launch .lnk for XenApp pnagent.exe, runs Internet Explorer remotely, and communicates with it through the clipboard using special keyboard shortcuts," according to Kaspersky's technical report on the attack.
They also were spotted performing other rookie-attacker mistakes: logging in RAM and files simultaneously and storing encryption keys in the same file.
Even so, Legezo says he thinks MontysThree is still fine-tuning and further developing its attack framework, so he's continuing to track the group closely.