Here we go again, but this time AI was not used as a weapon but rather as a vector. Anthropic was compromised (internal? external? does not matter at the moment). Kevin Beaumont put it most concisely, “Their Claude Code extension on Visual Studio Code and Cursor has malware in it, which creates a remote access Trojan to desktops.”

This is extremely serious and it is clear that Anthropic is doing what they can to fix the problem without telling their customers or the people who were using the extension. WTF, Anthropic? Bad security citizen much?

Read about the back door malware installed on Phorion’s alert: https://phorion.io/blog/offical-claude-code-vsx-compromise/. The extension, “drops a persistent SSH backdoor across macOS, Linux, and Windows.” Their advice states:

Organisations should immediately review their environments for use of Claude Code for VSCode 2.1.313 and engage incident response where use of the extension is discovered.

Beaumont’s writeup is here: Anthropic hacked to deliver remote access trojan to Claude developer laptops worldwide. Most salient point and why we’re writing this up here—“Anthropic has not informed customers, and silently deleted the backdoored version without telling anybody.”

Note that binance used this extension, and they were just spectacularly popped to the tune of billions of dollars (probably by the North Koreans). The C2 server used by the attackers has been taken down. We’re at the very tip of the iceberg here…

At BIML we have never been impressed with Anthropic’s FUD-filled, YOLO approach to security. They seem to think this is a game. It’s not. Heck, even if it is, they are losing.