An active threat actor is found targeting and compromising different companies. The attacker operates a new server hosting a large stockpile of malicious files. The adversary can deploy ransomware as well as steal credit card information via a point-of-sale malware and remotely managed compromised infrastructure. These files shows that these attackers were able to obtain a deep level of access to victims’ infrastructure using ransomware like the DopplePaymer, credit card capture malware like the TinyPOS, as well as some loaders that execute code delivered directly from the command and control (C2).
The adversary is resourceful and has a widespread infrastructure. A WinRAR self-extracting archive (SFX) is used to extract the ransomware and execute the following command:
On the same server a TinyPOS sample was also found. This malware is installed using a batch file.The batch file creates a scheduled task that will be executed every 6 hours.
The data going out is obfuscated using XOR operations with a hardcoded key of 0xcaef3d8a. The malware exfiltrates the hostname and the local IP of the infected system. It searches and parses targeted processes memory to retrieve credit card information, which is usually stored in tracks 1 and 2 of the magnetic strip of the credit card.
Other malicious tools hosted on the server include Mimikatz, a tool to retrieve Windows credentials from the memory, PsExec: A tool to remotely connect on Windows system (The attacker probably used it to pivot inside the infrastructure by using the credential previously retrieved.), Procdump: A tool to dump process. The attacker probably used it to dump the LSASS.exe process to then use with Mimikatz. The attacker likely was planning to carry out fake tech support scam to attempt to compromise infrastructure. This would likely be carried out by asking employees to execute specific commands or attempting to download the malware provided by the attacker.