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Malicious Claude Code extension on Cursor planted SSH backdoors

BleepingComputer
Actively Exploited
Malware

Overview

On October 29, a malicious version of the Claude Code extension for Visual Studio Code was available on Cursor's extension marketplace for about 11 hours. This compromised extension was designed to install persistent SSH backdoors, potentially affecting around 5,000 developers who downloaded it. The backdoors allow attackers to gain unauthorized access to affected systems, posing serious security risks to users' projects and data. The incident underscores the importance of scrutinizing third-party extensions and highlights the ongoing challenges in securing development environments. Developers are urged to remove the malicious extension and check their systems for any unauthorized access.

Key Takeaways

  • Active Exploitation: This vulnerability is being actively exploited by attackers. Immediate action is recommended.
  • Affected Systems: Claude Code VS Code extension, Cursor's extension marketplace
  • Action Required: Remove the malicious Claude Code extension and check for unauthorized access to your systems.
  • Timeline: Ongoing since October 29, 2023

Original Article Summary

A malicious version of Anthropic's Claude Code VS Code extension was distributed through Cursor's extension marketplace for approximately 11 hours on October 29, exposing up to 5,000 developers to malware designed to install persistent SSH backdoors. [...]

Impact

Claude Code VS Code extension, Cursor's extension marketplace

Exploitation Status

This vulnerability is confirmed to be actively exploited by attackers in real-world attacks. Organizations should prioritize patching or implementing workarounds immediately.

Timeline

Ongoing since October 29, 2023

Remediation

Remove the malicious Claude Code extension and check for unauthorized access to your systems.

Additional Information

This threat intelligence is aggregated from trusted cybersecurity sources. For the most up-to-date information, technical details, and official vendor guidance, please refer to the original article linked below.

Related Topics: This incident relates to Malware.

Read Original Article

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