# Cursor reports malicious Claude Code VS Code extension affecting up to 5,000 users

> Original title: We identified a security incident affecting a modified Claude Code VS Code extension accessed through our Cursor IDE extension marketplac...

- Source: Cursor
- Published: 2026-10-30T07:46:39.000Z
- Bad Influence: https://badinfluence.news/items/dhefksqhqxt62f0t6wrtjlq79
- Original: https://x.com/cursor_ai/status/2116074289053175808

## Summary

Cursor says a modified Claude Code VS Code extension distributed through its IDE extension marketplace affected at most 5,000 users. Cursor says Anthropic did not develop the malicious version, and that the incident does not affect other marketplace extensions, Grok Bot, Grok, or other SpaceXSI products. Cursor took the marketplace down, neutralized the malware with relevant providers, and reinstated it, and asks users to update to Claude Code for VS Code version 2.1.314.

## Post

We identified a security incident affecting a modified Claude Code VS Code extension accessed through our Cursor IDE extension marketplace, impacting at most 5,000 users. This malicious version of the extension was not developed by Anthropic. It does not impact other extensions downloaded from the http://cursor.com/marketplace, Grok Bot, Grok or our other SpaceXSI products.

In response, we took down our extension marketplace this afternoon, worked with relevant providers to neutralize the malware, and have reinstated the marketplace after confirming there is no further risk.

If affected, please review instructions in this blog post to understand how to find the malicious package and establish a path to mitigate any potential impact. We are asking all customers update to Claude Code for VS Code version 2.1.314: https://cursor.com/blog/claude-code-extension-security-notice