Reconnaissance is the key part of a successful attack, Andariel Group which is part of well-known notorious Lazarus Group uses new techniques to find the right targets for their exploit.
The Andariel Group injects their scripts in compromised South Korean websites and collects ActiveX object information before they are to use their exploit.
Andariel group is active for a couple of months. According to IssueMakersLab, the group used an ActiveX zero-day exploit for watering hole attacks on South Korean websites on last May—they called this “Operation GoldenAxe”.
Security researchers from Trend Micro spotted that on June 21 Andariel group injected a new script into four compromised South Korean websites for gathering information. Researchers believe that new script was trying to collect the different ActiveX object and that could be for their next targets for a watering hole exploit attack.
The reconnaissance lasted between June 21 to 27 and the scripts found injected with the compromised Korean non-profit organization and Korean local government labor union websites.
According to researchers, the injected malicious script came form Andariel group as they have the same obfuscation methods and similar to the samples.
Attackers used the script to collect the user information such as visitors’ browser type, system language, Flash Player version, Silverlight version, and multiple ActiveX objects.
Reconnaissance Flow – Andariel Group
1. Attackers compromise the website and inject’s malicious scripts.
2. When a user access the compromised website the malicious script will execute.
3. The Executed malicious script collects the information and sends to the remote server.
4. Attacker get’s information about the target.
When compared to the previous scripts the newly inject script contains two additional ActiveX objects “DSDOWNCTRL.DSDownCtrlCtrl.1” related to Digital Rights Management and “WSACTIVEBRIDGEAX.WSActiveBridgeAXCtrl.1” that related to South Korea-based voice conversion software that used by many public and government institutions.
Also, the new script adds WebSocket along with new ActiveX objects to perform verification with Chrome and Firefox.
“This shows that the attacker has expanded his target base, and is interested in the software itself and not just their ActiveX objects. Based on this change, we can expect them to start using attack vectors other than ActiveX.”
Trend Micro published a blog post with analysis report and comparison between the previous and new script.