# CVE-2026-4496: sigmade Git-MCP-Server gitUtils.ts child_process.exec os command injection

> Local attackers can execute arbitrary OS commands via the show_merge_diff function in the Git-MCP-Server tool.

- **Severity:** Medium 4.8 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P`)
- **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:** No
- **Published:** 20 Mar 2026
- **Updated:** 25 Mar 2026
- **Also known as:** GHSA-m2rq-r53v-mvq4

## What is CVE-2026-4496?

CVE-2026-4496 is a medium-severity command injection vulnerability in sigmade Git-MCP-Server, published on 20 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A vulnerability was found in sigmade Git-MCP-Server up to 785aa159f262a02d5791a5d8a8e13c507ac42880. Affected by this vulnerability is the function child_process.exec of the file src/gitUtils.ts of the component show_merge_diff/quick_merge_summary/show_file_diff. The manipulation results in os command injection. The attack must be initiated from a local position. The exploit has been made public and could be used. This product operates on a rolling release basis, ensuring continuous delivery. Consequently, there are no version details for either affected or updated releases. It is advisable to implement a patch to correct this issue. The vendor was contacted early about this disclosure but did not respond in any way.

Weakness: CWE-78 (Improper Neutralization of Special Elements used in an OS Command), CWE-77 (Improper Neutralization of Special Elements used in a Command)

## Which versions are affected by CVE-2026-4496?


## How do I fix CVE-2026-4496?

No fix has been published for CVE-2026-4496 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-4496 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-4496 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-4496 and fix it if it is affected.

What it is: CVE-2026-4496 is a medium-severity command injection vulnerability in sigmade Git-MCP-Server, published on 20 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-4496 exists.

Affected product: sigmade Git-MCP-Server. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2026-4496/ (Markdown: https://insights.sbomify.com/CVE-2026-4496/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-4496
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-4496
- OSV: https://osv.dev/vulnerability/CVE-2026-4496

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-4496/
Summaries are generated and may contain mistakes; the official description above is the record.