Mac Malware Masquerade: How ClickFix Hijacked Homebrew Installs to Steal Developer Secrets

It started with a typo - just a single misplaced letter in a web address. For countless macOS developers, however, that slip was all cybercriminals needed to open the door. In a chilling new wave of attacks, threat actors have weaponized the “ClickFix” technique, transforming the well-worn Homebrew installation process into a vector for delivering a powerful new infostealer dubbed Cuckoo Stealer. The result? A masterclass in deception that blends seamlessly into the daily routines of even the savviest users.

The Anatomy of a Deception

The campaign’s genius lay in its simplicity. By registering domains like homabrews[.]org - virtually indistinguishable from the official Homebrew site - and replicating its design, attackers created a nearly perfect illusion. The only clue: a subtle difference in the URL. Centered on the page was the familiar “install Homebrew” command with a “Copy” button. But this time, the command quietly swapped out the legitimate download source for a malicious one, setting the stage for compromise.

Developers, conditioned to trust and quickly execute curl | bash commands for software installs, became unwitting accomplices. Upon pasting the command into Terminal, a loader script ran, mimicking the legitimate Homebrew installer. Before proceeding, it entered a password-harvesting loop, prompting for the user’s macOS credentials with convincing error messages, just like the real sudo flow. Once captured, the loader fetched a secondary binary, installed persistence as a fake Homebrew updater, and removed quarantine attributes to bypass Gatekeeper protections.

Cuckoo Stealer: The Mac Intruder

The second stage, Cuckoo Stealer, proved especially dangerous. It established encrypted channels to command-and-control servers, received remote instructions, and aggressively harvested data. Targets included browser sessions, Keychain secrets, Apple Notes, Discord and Telegram tokens, VPN and FTP configs, Steam sessions, and a broad spectrum of cryptocurrency wallets. The malware even took silent screenshots and browsed user files, all while operating under the guise of normal system activity.

Locale checks ensured the malware avoided CIS-region systems, hinting at financial motives and a professional operation. Researchers quickly identified a wider network of similar typosquats and terminal-phishing pages, all exploiting the copy-paste trust model ingrained in the developer community.

Lessons for the Mac Community

This attack is a stark reminder: convenience can be a double-edged sword. The very habits designed to streamline developer workflows have become a potent attack surface. Defenders are urged to block known typosquats, scrutinize raw download domains in curl commands, and monitor for suspicious LaunchAgents masquerading as trusted tools. As attackers raise their game, so too must the vigilance of the macOS ecosystem.

WIKICROOK

• Typosquatting: Typosquatting is when attackers use lookalike names of trusted sites or software to trick users into visiting fake sites or downloading malware.
• Infostealer: An infostealer is malware designed to steal sensitive data - like passwords, credit cards, or documents - from infected computers without the user's knowledge.
• Persistence: Persistence involves techniques used by malware to survive reboots and stay hidden on systems, often by mimicking legitimate processes or updates.
• LaunchAgent: A LaunchAgent is a macOS file that lets programs run automatically at user login, often used by both legitimate apps and malware for persistence.
• Command: A command is an instruction sent to a device or software, often by a C2 server, directing it to perform specific actions, sometimes for malicious purposes.

In a world where a single click can compromise an entire system, the ClickFix campaign is a wake-up call. Trust, once the foundation of developer productivity, has become the very thing cybercriminals exploit. For macOS users, the message is clear: look twice before you paste - and never underestimate the power of a typo.