Threat actors have been using commercial command and control frameworks — or illegal copies of them — like Cobalt Strike, Sliver, Metasploit and others, for years to further their attacks.
A new open-source framework named Havoc — created to help penetration testers — is now being exploited by at least one hacker, according to researchers at Zscaler, who have seen it targeting an unnamed government organization.
The tools in Havoc, which allow a user to communicate with a command and control server, are ideal for an attacker.
“While C2 [command and control] frameworks are prolific,” the researchers said this week, “the open-source Havoc framework is an advanced post-exploitation command and control framework capable of bypassing the most current and updated version of Windows 11 Defender due to the implementation of advanced evasion techniques such as indirect syscalls and sleep obfuscation.”
The threat actor abusing Havoc used a devious method for delivering the payload, the Havoc Demon. Somehow — the researchers don’t explain how — a compressed file named ZeroTwo.zip was delivered to the victim. It contains two files: A decoy document, which in this case was a document describing “ZeroTwo,” a fictional character in the Japanese anime television series Darling in the Franxx; and what would appear to be a screen saver file called “character.scr”, which leads to downloading the Havoc Demon Agent. It also downloads a JPG image of a character from the TV series, which helps to hide what’s really going on.
The researchers don’t say, but one might assume a phishing message would be sent to an employee or employees of an organization, offering an image from the TV series in hopes that a victim would download it.
The downloaded payload includes a shellcode loader, which is signed using Microsoft’s Digital certificate to fool Windows. Among other things, the loader disables Windows’ Event Tracing capability.
The Havoc C2 framework campaign highlights the importance of proper cybersecurity measures in today’s digital world, say the researchers. Organizations have to be vigilant and protect their IT systems, they say. “With the rise of technology, the need for robust security solutions becomes increasingly vital, and organizations must take proactive steps to ensure the safety of their systems and data.”