Tampered Claude Code extension in Cursor marketplace stole host data
Original title: Malicious Claude Code extension in Cursor's marketplace attempted remote access and data theft
Cursor says the listing was live about eleven hours and may have reached 5,000 users before the marketplace was taken offline.
A tampered Claude Code extension was available in Cursor's VS Code marketplace on Thursday for about eleven hours. Cursor says it may have affected up to 5,000 users and that Anthropic did not develop it. The extension collected hostname, username, operating system, and public IP, and tried to set up remote access that Cursor says likely failed without administrator privileges. Cursor removed the extension, took the marketplace offline, neutralized the malware with providers, and later restored the marketplace, saying no other extensions were affected.
Unconfirmed: The reach of up to 5,000 users and the claim that remote access likely failed are Cursor's statements.
- The tampered listing was available for about eleven hours.
- Collected data included hostname, username, OS, and public IP.
- Remote access likely required admin rights and failed on most machines, Cursor says.
- Cursor says no other marketplace extensions were affected.
Impact: Host identity and public IP collected; remote access attempted
| Product | Affected |
|---|---|
| Cursor Claude Code extension | — |
- 1.Remove the Claude Code extension if it was installed from Cursor's marketplace on Thursday.
- 2.Review machines that ran it for unexpected remote-access software.
- Vendors
- Cursor
- Products
- Claude Code
- Organizations
- Anthropic
From the original article
1 min read at the-decoder.comA tampered Claude Code extension was live on the Cursor marketplace for about 11 hours, affecting up to 5,000 users. It tried to steal user data and set up remote access. Cursor took the entire marketplace offline and reinstated it after confirming there was no further risk.
By Matthias Bastian · the-decoder.com
A short excerpt; the article and its images belong to the publisher. Summary, key facts and assessment above are AI-written from the article and can be wrong.