Claude Desktop app was reportedly found changing browser access settings without consent

The Claude Desktop app for macOS has recently been reported to quietly alter browser level settings behind the user’s back. Reports say the app installs a Native Messaging manifest that pre authorizes communication between certain browser extensions and its local binary without any explicit consent. Even worse, it reportedly places configuration files for multiple Chromium based browsers, including some the user doesn't even have installed yet.

According to the report, the file com.anthropic.claude_browser_extension.json registers a local executable and pre approves three extension identifiers, effectively giving them a future bridge into the Claude app. Privacy consultant Alexander Hanff has called the behavior a dark pattern, arguing that it bypasses informed consent and could conflict with the EU’s ePrivacy Directive. Its worth noting that Native Messaging itself is a legitimate browser integration method, but the real issue here is the silent and preemptive authorization, which weakens normal browser security expectations and expands the attack surface if an approved extension is ever abused.

Anthropic presents these integrations as part of Claude’s agentic features, which are meant to let the app automate tasks, access files, and interact with the browser. But security experts say this kind of browser to local app bridge should be treated as a sensitive configuration, not something slipped in quietly during installation. That said, some users in Reddit argue the report may overstate what the manifest actually does, since by itself it doesn't install extensions or directly let Claude control a browser unless the matching extension is later installed by the user.