A sophisticated campaign targeting macOS users has been discovered, utilizing a stealthy method to deliver information-stealing malware through DNS records. The hackers disguise malicious scripts within cracked applications, repackaged as PKG files, ultimately containing a trojan. The infection process involves victims downloading and executing the malware, assuming it to be an activator for the cracked app. The malware, once granted permission, contacts a command and control server via a deceptive domain name hidden in DNS requests, allowing the attackers to hide their activity and download the payload disguised as TXT records.
The cybersecurity firm Kaspersky identified this covert campaign and analyzed its stages. The malware, disguised as a bogus Activator window, requests the administrator password from victims. Upon obtaining permission, the malware executes a tool and checks for Python 3 on the system, installing it if absent. The malware then contacts a command and control server through DNS requests using a unique method that hides its activity within normal traffic. The DNS server responds with base64-encoded fragments of an AES-encrypted Python script, allowing the malware to download and execute a backdoor script, establishing persistence and gathering information about the infected system.
The campaign’s unique feature involves using DNS records to deliver the payload, hiding malicious scripts within TXT records retrieved from the DNS server. This method helps the threat actors conceal their activity and evade detection. The downloaded script acts as a downloader for another Python script that provides backdoor access and transmits system information to the attacker’s command and control server. Additionally, the malware targets Bitcoin Core and Exodus wallets, replacing them with backdoored copies. Users falling victim to this campaign risk having their wallet information sent to the attacker’s server, potentially leading to unauthorized access and theft.
Kaspersky’s analysis highlights the continuous development of the backdoor script, as the command and control server returned upgraded versions. The campaign serves as a reminder of the risks associated with using cracked applications, which remain a common vector for malware delivery. The attackers demonstrate ingenuity by employing new techniques, such as hiding payloads within DNS records, emphasizing the need for users to exercise caution and employ security best practices to avoid falling victim to sophisticated cyber threats.
