GitSpawn Exposes Persistent Git Config Execution Risks in Coding Agents
Manifold Security released GitSpawn, detailing eight vulnerabilities across seven coding agents where opening a folder triggers arbitrary code execution via Git configuration before any user prompt. The core issue stems from the core.fsmonitor setting in .git/config, which Git executes during index updates like git status or git diff. While vendors including Anthropic patched Claude Code in version 2.1.196, the fix only blocks agent-initiated calls and leaves manual Git commands or other tools vulnerable. Additional vectors include nested bare repositories tracked under CVE-2026-45033 affecting GitHub Copilot CLI and unpatched agents such as Qwen Code and Grok Build. The researcher also released the Stroq tool to inspect repositories for dangerous settings like core.fsmonitor and postinstall scripts before opening them. The findings highlight that repository trust mechanisms from 2021 remain bypassed by modern AI coding tools.
HabrSep 16, 2026Translated from Russian