Introduction

In recent weeks, I've searched for pages impersonating Claude that distribute malware. In recent weeks, I've reliably found these sites through malicious ads in Google searches that lead to these pages, often concealed in URLs for sites.google[.]com, such as this example from 2026-05-11.

These fake Claude pages generally show instructions for macOS malware when viewed through a macOS system, and they will show instructions for Windows malware when viewed through a Windows system. Today's dairy shows an example of Windows malware from one of these pages seen on Monday, 2026-05-25. Based on the C2 domain for post-infection traffic, this appears to be an infection for ACR Stealer.

Images


Shown above: Web page impersonating Claude with a button to "Download for Windows."


Shown above: Instructions to install Claude on Windows are actually instructions that will infect a vulnerable computer with malware.


Shown above: Traffic from a Windows host when following instructions from the fake Claude download page.

Indicators of Compromise

Fake Claude download page:

From the above page, URL for the initial download:

Follow-up download:

A further download:

Domain for post-infection HTTPS traffic to C2 server:

Initial download:

SHA256 hash: 70b5ecc110e074dbca92932c0e840ea3492ea0a43c3f215b71392c12b02213b2

Follow-up download, PowerShell script:

SHA256 hash: a14c3ecf5eb3d2543358482e43dc765dbf9ee7a4bec7571f5ecb8829ca719692

A further download:

SHA256 hash: 47fa746422f1bf6b7712dc6803378e6a995488007193a7441d790f70d204728f

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Bradley Duncan
brad [at] malware-traffic-analysis.net

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