# CVE-2026-27735: mcp-server-git : Path traversal in git_add allows staging files outside repository boundaries

> Attackers can stage files outside the repository boundaries via path traversal in the git_add tool of the MCP Git server.

- **Severity:** Medium 6.4 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 25 Feb 2026
- **Updated:** 26 Feb 2026
- **Also known as:** GHSA-vjqx-cfc4-9h6v, MINI-mch8-8h85-3j5v, PYSEC-2026-2630

## What is CVE-2026-27735?

CVE-2026-27735 is a medium-severity path traversal vulnerability in modelcontextprotocol servers, published on 25 Feb 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

Model Context Protocol Servers is a collection of reference implementations for the model context protocol (MCP). In mcp-server-git versions prior to 2026.1.14, the git_add tool did not validate that file paths provided in the files argument were within the repository boundaries. Because the tool used GitPython's repo.index.add() rather than the Git CLI, relative paths containing `../` sequences that resolve outside the repository were accepted and staged into the Git index. Users are advised to upgrade to 2026.1.14 or newer to remediate this issue.

Weakness: CWE-22 (Improper Limitation of a Pathname to a Restricted Directory)

## Which versions are affected by CVE-2026-27735?

3 open source packages ship an affected version, including mcp-server-git. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `mcp-server-git` | PyPI | All versions | 2026.1.14 |
| `mcp-server-git` | PyPI | All versions | 2026.1.14 |
| `mcp-server-git` | PyPI | All versions | 2026.1.14 |

Products: Lfprojects Model Context Protocol Servers.

## How do I fix CVE-2026-27735?

Upgrade mcp-server-git to 2026.1.14 or later.

## Is CVE-2026-27735 being exploited?

There is no known exploitation of CVE-2026-27735 in the wild and no public exploit code.

## Other vulnerabilities in modelcontextprotocol servers

- [CVE-2025-68143](https://insights.sbomify.com/CVE-2025-68143/): mcp-server-git's unrestricted git_init tool allows repository creation at arbitrary filesystem locations (medium 6.5)
- [CVE-2025-68145](https://insights.sbomify.com/CVE-2025-68145/): mcp-server-git has missing path validation when using --repository flag (medium 6.4)
- [CVE-2025-68144](https://insights.sbomify.com/CVE-2025-68144/): mcp-server-git argument injection in git_diff and git_checkout functions allows overwriting local files (medium 6.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-27735 and fix it if it is affected.

What it is: CVE-2026-27735 is a medium-severity path traversal vulnerability in modelcontextprotocol servers, published on 25 Feb 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-27735 in the wild and no public exploit code.

Affected packages and fixed versions:
- mcp-server-git (PyPI): affected all versions; fixed in 2026.1.14
- mcp-server-git (PyPI): affected all versions; fixed in 2026.1.14
- mcp-server-git (PyPI): affected all versions; fixed in 2026.1.14

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-27735/ (Markdown: https://insights.sbomify.com/CVE-2026-27735/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-27735
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-27735
- OSV: https://osv.dev/vulnerability/CVE-2026-27735

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-27735/
Summaries are generated and may contain mistakes; the official description above is the record.