Developers are the primary targets of a new malvertising campaign leveraging Google Ads (opens in a new tab) to distribute the Amatera infostealer (opens in a new tab). The attack took place on both Windows and macOS. By impersonating Anthropic’s “Claude Code” CLI tool, attackers are tricking technical users into executing malicious one-line installation commands that silently drain credentials and cryptocurrency wallets.
The InstallFix Attack
Researchers first identified the campaign on March 6, 2024. The attack utilizes a social engineering tactic known as InstallFix. This is an evolution of the “ClickFix” (opens in a new tab) method, where users are manipulated into manually running the malware on their own computers.
How the deception works:
Attackers purchase Google Ads for keywords like “Claude Code install” and “Claude Code CLI.”
Victims land on a site that is a near-perfect replica of the official page. It mirrors the branding, documentation sidebar, and layout of the real page.
To maintain the illusion, every link on the fake page, including the Terms of Service, About, etc., redirects to the legitimate website.
The only malicious element is the installation command itself. The page provides custom malicious strings for macOS, Windows PowerShell, and Windows CMD.
Amatera: A “Silent” Threat to Developers
Once the user pastes the command into their terminal, the malware harvests data in the background without triggering standard endpoint alerts or system warnings. It can then access your browser data like saved passwords, session cookies, and autofill information. Financial assets, including cryptocurrency wallets and extension data. It can also access session tokens that allow attackers to bypass Multi-Factor Authentication (MFA) and hijack corporate accounts once downloaded.
Why Traditional Security is Failing
The main reason this malvertising campaign is so prevalent is that it bypasses the most common corporate defenses:
Email Filtering: Since the user initiates the search and clicks a trusted Google result, there is no phishing email for security software to intercept.
Trusted Hosting: Attackers host these clone pages on legitimate platforms like Squarespace, Cloudflare Pages, and Tencent EdgeOne, which often bypass automated URL blocklists.
Low Barriers to Entry: Because Amatera is sold as a service, attackers don’t need a lot of technical skills to launch parallel campaigns against other popular developer tools like OpenClaw.
How to Protect Your Environment
As non-technical users increasingly experiment with agentic AI tools, the surface area for these attacks is expanding. Developers and IT teams should adopt the following approach to CLI installations:
Audit the One-Liner: Before hitting Enter on any curl or wget command, manually inspect the domain embedded in the string. If it doesn’t match the official project domain, leave immediately.
Disable Sponsored Results: Use browser extensions or DNS filtering to hide sponsored search results, which are the primary delivery vector for this malware.
Use Official Repositories: Whenever possible, install tools directly from verified GitHub repositories or official package managers (npm, brew, etc.) rather than following search engine links.
Conclusion: Protect your brand from hackers
If you are looking to effectively protect your online platform and maintain the trust of your developer community, contact our team today (opens in a new tab). Learn how to start securing your ad network or website against the next generation of infostealer campaigns and ensure your users remain safe from high-stakes digital theft.
