Preliminary research

Open and Shut: Remote Code Execution in opencode via MCP OAuth

Eilon Cohen · Pillar Security · 19 October 2026

AI-collected research leads through 3 November 2026, including a November–October–September missed-article review and a targeted multilingual search alongside earlier community-source sweeps. Unranked, incomplete, not community-vetted, and subject to change.

A normal-looking HTTPS OAuth authorization endpoint reaches PowerShell double-quoted interpolation through an older URL-opening dependency. URL parsing and scheme allowlists do not fix the shell boundary.

Record

Researcher

Eilon Cohen

Published by

Pillar Security

Date

19 October 2026

In the archive

• Collected in the 2026 preliminary research sweep

Related sources

• Earlier MCP OAuth exploitation
• 2023 URL-opening issue

Tags

• mcp
• oauth
• command-injection
• rce
• powershell
• owasp-a03-2021
• owasp-a07-2021

This page is the archive's own catalogue record. The research is the work of Eilon Cohen, first published at the original source. Preserved copies are kept so the citation survives its host.