logoalt Hacker News

xx_ns • today at 11:29 AM • 4 replies • view on HN

I think it should be important to note that this affected the Claude Code extension on the Open VSX extension registry (and by extension, the Cursor marketplace). From what is currently known, the build on the official marketplace was/is clean.

EDIT: I am now actually unsure if this is the case. From what I can see, all of the write-ups mention the Cursor marketplace and Open VSX specifically, but make no explicit mention of the official Microsoft registry.

EDIT 2: The version that was compromised (2.1.313) seems to have never been published on the official Microsoft registry. As per the documentation [1], unpublished versions should still be discoverable:

> When you unpublish an extension, the Marketplace preserves the extension statistics. The extension remains publicly discoverable and available via an existing API.

[1]: https://code.visualstudio.com/api/working-with-extensions/pu...


Replies

ddworken • today at 3:09 PM

Dworken from Anthropic here: This only impacted the extension as it was hosted on the Cursor marketplace. It did not impact the official VS Code extension marketplace or OpenVSX. Users of Claude Code on VS Code are not impacted by this issue.

mrweasel • today at 11:37 AM

You mean on the Microsoft VSCode marketplace? The version has been yanked from there as well, but that could just be a precaution and to avoid confusion about having the same version be simultaneously infected and not infected.

This very much illustrates the danger of just carelessly installing untrusted software on your machine. In this case it happens to be code from Anthropic, but it could have been almost anyone. I'll be very interested in see the explanation from Anthropic, because of all the extension developers they should have the best tools for finding issues like this. LLMs have proven pretty good at finding security issues, so did they simply not let their own AI tools vet the code before shipping it? Or was the extension infected later, because in that case every single extension on Open VSX could be at risk.

➕ show 1 reply
misnome • today at 11:49 AM

The screenshot is of the official marketplace

thevinter • today at 11:37 AM

Do you have any sources? OP claims that it *also* affects Open VSX

➕ show 4 replies