An ongoing social engineering campaign, suspected to be linked to the Black Basta ransomware group, is currently targeting users through a combination of email bombs and fraudulent support calls. The attackers use these methods to convince individuals to install AnyDesk, a legitimate remote access software. Once installed, AnyDesk acts as a channel for deploying additional malware and exfiltrating sensitive data. The campaign employs a variety of tactics to deceive users.
Initially, victims receive an email bomb and follow-up calls via Microsoft Teams, where attackers offer fake solutions. The attack chain then persuades users to download AnyDesk, which is used to install further payloads, including the malware dropper SystemBC. This dropper facilitates additional malicious activities, such as credential theft and system compromise.
As part of the attack, the malware includes an executable named AntiSpam.exe, which pretends to be an update for email spam filters and prompts users to enter their Windows credentials. This step is followed by the execution of various binaries, DLL files, and PowerShell scripts, including a Golang-based HTTP beacon, SOCKS proxy, and SystemBC itself. These components work together to establish contact with remote servers and extend the reach of the malware. To mitigate the risks posed by this campaign, experts recommend blocking all unauthorized remote desktop solutions and being vigilant about suspicious phone calls or messages that claim to be from IT support.
The recent emergence of various loader strains and the weaponization of fake QR codes highlight the evolving nature of phishing and social engineering attacks, underscoring the need for advanced detection and preventative measures.
Reference:
- https://www.rapid7.com/blog/post/2024/08/12/ongoing-social-engineering-campaign-refreshes-payloads/
