CVE-2026-45033: GitHub Copilot CLI: Nested Bare Repository Can Execute Arbitrary Commands via core.fsmonitor

A security vulnerability has been identified in GitHub Copilot CLI where a malicious bare git repository nested inside a project directory can achieve arbitrary code execution when the agent performs git operations. By exploiting git’s automatic bare repository discovery during directory traversal, an attacker can set core.fsmonitor or other executable config keys to run arbitrary commands without user awareness or approval.