OpenCode Flaw Lets Malicious MCP Servers Execute Code During Sign-In on Windows and WSL
- ID
- 38258
- Status
- summarized
- Published
- 22 Oct 2026, 6:44 PM
- Fetched
- 22 Oct 2026, 8:00 PM
- Provider
- The Hacker News
- Category
- security
- Original URL
- https://thehackernews.com/2026/10/opencode-flaw-lets-malicious-mcp.html
- Source URL
- https://feeds.feedburner.com/TheHackersNews
Summary
- Score
- 6.5
- Created
- 22 Oct 2026, 8:01 PM
- Tags
- Audience
- developersvibe_codersai_agent_usersai_ml_learners
What happened
The Hacker News reports a flaw in OpenCode where malicious MCP servers can execute code during the sign-in flow, affecting Windows and WSL. The write-up is dated 22 Oct 2026 and is scoped to those two platforms. The supplied excerpt contains no CVE ID, affected version range, or patch status, so the specific trigger and fix are not verifiable from this text.
Why it matters
If you run OpenCode on Windows or WSL and add MCP servers from GitHub, marketplaces, or a colleague's config, this reframes 'installing an MCP server' as running untrusted code at the moment you authenticate. The excerpt does not state whether a fix has shipped, so check OpenCode's release notes for your exact version before assuming you're covered, and avoid signing in to OpenCode with MCP servers you haven't read the source of.
Discussion angle
MCP's trust model: adding a server is equivalent to running someone else's code with your credentials, and the sign-in/OAuth step is now an execution path — worth asking who in the room reviews MCP server source before adding it to a project.