Backdoors in official Claude Code extensions
- ID
- 41172
- Status
- summarized
- Published
- 30 Oct 2026, 7:05 PM
- Fetched
- 30 Oct 2026, 9:31 PM
- Provider
- Hacker News
- Category
- dev-community
- Original URL
- https://cyberplace.social/@GossiTheDog/117528831681803563
- Source URL
- https://hnrss.org/best
Summary
- Score
- 8.5
- Created
- 30 Oct 2026, 9:32 PM
- Tags
- Audience
- developersvibe_codersai_agent_users
What happened
Kevin Beaumont's post alleges Anthropic was compromised and that the official Claude Code extension for VS Code and Cursor contains malware that installs a remote access Trojan on developer desktops. The linked Phorion advisory preview says it found a backdoor in the official Claude Code for VS Code extension bundle distributed on Open VSX that drops a persistent SSH backdoor across macOS, Linux, and Windows. The post and preview give no version numbers, infection timeline, or Anthropic response; the Hacker News thread drew 315 points and 79 comments.
Why it matters
If you installed the Claude Code VS Code/Cursor extension from Open VSX rather than the Microsoft marketplace, the specific claim is a persistent SSH backdoor on macOS, Linux, or Windows — so check your install source and treat that machine as untrusted until you have looked for the indicators in the Phorion write-up. Teams that standardise on Claude Code should decide now whether extension provenance (Open VSX vs marketplace) is an allowed-source policy item, because this is an agent tool that typically runs with shell access on developer laptops.
Discussion angle
The extension was on Open VSX, not the Microsoft marketplace — how many of us actually know which registry our editor pulled an AI coding extension from, and would an SSH backdoor on a dev laptop be noticed before it was used?