# CVE-2026-40520: FreePBX api module Command Injection via GraphQL

> Authenticated attackers can execute arbitrary commands on the host via GraphQL mutations in the FreePBX API module.

- **Severity:** High 8.6 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 21 Apr 2026
- **Updated:** 24 Sep 2026
- **Also known as:** CVE-2026-41410, GHSA-h2vx-h73q-6q6w

## What is CVE-2026-40520?

CVE-2026-40520 is a high-severity command injection vulnerability in FreePBX api, published on 21 Apr 2026. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

FreePBX api module version 17.0.8 and prior contain a command injection vulnerability in the initiateGqlAPIProcess() function where GraphQL mutation input fields are passed directly to shell_exec() without sanitization or escaping. An authenticated user with a valid bearer token can send a GraphQL moduleOperations mutation with backtick-wrapped commands in the module field to execute arbitrary commands on the underlying host as the web server user.

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

## Which versions are affected by CVE-2026-40520?

It affects 1 product.


Products: Freepbx Api.

## How do I fix CVE-2026-40520?

No fix has been published for CVE-2026-40520 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-40520 being exploited?

There is no known exploitation of CVE-2026-40520 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-40520 and fix it if it is affected.

What it is: CVE-2026-40520 is a high-severity command injection vulnerability in FreePBX api, published on 21 Apr 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-40520 in the wild and no public exploit code.

Affected product: FreePBX api. 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-2026-40520/ (Markdown: https://insights.sbomify.com/CVE-2026-40520/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-40520
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-40520
- OSV: https://osv.dev/vulnerability/CVE-2026-40520

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-40520/
Summaries are generated and may contain mistakes; the official description above is the record.