CVE-2026-45033 GitHub Copilot CLI: Nested Bare Repository Can Execute Arbitrary Commands via core.fsmonitor
A malicious nested bare git repository can trigger arbitrary command execution via git config keys during Copilot CLI operations.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-45033?
CVE-2026-45033 is a high-severity command injection vulnerability in github copilot-cli, published on 13 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
GitHub Copilot CLI brings AI-powered coding assistance directly to your command line. Prior to 1.0.43, 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. The vulnerability arises because git's core.fsmonitor config key (and 15+ similar keys such as core.hookspath, diff.external, merge.tool, etc.) can specify arbitrary shell commands that git will execute as part of normal operations like status, diff, or rev-parse. This vulnerability is fixed in 1.0.43.
Weakness: CWE-696
Which versions are affected by CVE-2026-45033?
2 open source packages ship an affected version, including @github/copilot. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
@github/copilot npm | All versions | 1.0.43 |
@github/copilot npm | All versions | 1.0.43 |
Products include Github Copilot-Cli.
How do I fix CVE-2026-45033?
Upgrade @github/copilot to 1.0.43 or later.
Upgrade, and pass arguments to programs as a list instead of through a shell. More about Command injection.
Is CVE-2026-45033 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-45033 exists.
Public exploit code: 1 proofs of concept on GitHub.
Sources
Also known as GHSA-9ccr-r5hg-74gf.