Patch Gap

AI tools · updated Oct 27, 2026

OpenCode AI helper on Windows: a bad connected tool could run code when you sign in

Patched: update nowCriticalUnconfirmed

Last checked · Check before installing; only use the official link.

OpenCode is an AI helper that works with code. It can connect to outside tools (called MCP servers). On Windows and in WSL, a bad or hijacked tool could make OpenCode run a command on your computer when you start a sign-in to that tool. News reports say version 1.18.33 fixes it, but OpenCode's makers did not announce it.

Status
Patched: update now
Being attacked?
No[2]
Severity
Critical
Updated

No report that anyone has used this bug. Severity: Proposed 9.8 by the researchers at Pillar Security. There is no official score. First reported .

Unconfirmed: OpenCode's makers did not publish a security notice or a CVE. The fix version comes from the researchers' report and the project's release page, which does not mention a security fix.

Am I affected?

You may be at risk if you use OpenCode on Windows (or in WSL) between version 1.0.137 and 1.18.32 and you connect it to outside tools that need sign-in. Mac and Linux are not affected, according to the report.

AppDeviceAffectedFixed in
OpenCodeWindowsOpenCode 1.0.137 to 1.18.32 on Windows and WSL (per researchers)1.18.33[1]

How to check your version

These checks only look. They do not change anything on your computer.

OpenCode on Windows

Easy way: Open PowerShell and type the command below.

Or type this in PowerShellRead-only. It only reads the version and changes nothing.

opencode --version

How to fix it

  1. Update OpenCode to 1.18.33 or newer.
  2. Check that opencode --version shows the new version.
  3. Only connect OpenCode to outside tools you trust. Do not start a sign-in to a tool you do not trust.

More on each app: Is my OpenCode up to date?

Official links

Check before installing, and only use these official links or the app's own update button.

For AI agents

This page as data: /incidents/opencode-windows-sign-in-code-run.json. All problems: /feed.json. Use read-only checks only, and ask before installing anything.

Tracking numbers (CVE): None

Sources

  1. MakerOpenCode release v1.18.33 (Sep 28, 2026)
  2. NewsThe Hacker News: OpenCode flaw lets malicious MCP servers run code on Windows and WSL (Oct 22, 2026)

"Maker", "CISA", "NVD", "GitHub advisory" and "Official notice" are official sources. "Researcher" and "News" are extra context.