# CVE-2026-27938: WPGraphQL Repo Vulnerable to Command Injection via Unsanitized GitHub Actions Expression in Release Workflow

> Attackers can execute arbitrary commands on CI runners by injecting shell code into pull request bodies during release workflows.

- **Severity:** High 7.7 (`CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 26 Feb 2026
- **Updated:** 26 Feb 2026
- **Also known as:** GHSA-4q9f-mjxf-rx7x

## What is CVE-2026-27938?

CVE-2026-27938 is a high-severity command injection vulnerability in wp-graphql, published on 26 Feb 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

WPGraphQL provides a GraphQL API for WordPress sites. Prior to version 2.9.1, the `wp-graphql/wp-graphql` repository contains a GitHub Actions workflow (`release.yml`) vulnerable to OS command injection through direct use of `${{ github.event.pull_request.body }}` inside a `run:` shell block. When a pull request from `develop` to `master` is merged, the PR body is injected verbatim into a shell command, allowing arbitrary command execution on the Actions runner. Version 2.9.1 contains a fix for the vulnerability.

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

## Which versions are affected by CVE-2026-27938?


## How do I fix CVE-2026-27938?

No fix has been published for CVE-2026-27938 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-27938 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-27938 exists.

Public exploit code:

- Security-research reproduction of CVE-2026-27938 / GHSA-4q9f-mjxf-rx7x (GitHub Actions expression injection in release workflows) — snapshot of wp-graphql/wp-graphql at b216fe22f3a119f256511ec7353f536fee6886ac (github_poc): https://github.com/pvharmo2/gha-lab-a7f6217d26

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-27938 and fix it if it is affected.

What it is: CVE-2026-27938 is a high-severity command injection vulnerability in wp-graphql, published on 26 Feb 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-27938 exists.

Affected product: wp-graphql. 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-2026-27938/ (Markdown: https://insights.sbomify.com/CVE-2026-27938/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-27938
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-27938
- OSV: https://osv.dev/vulnerability/CVE-2026-27938

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-27938/
Summaries are generated and may contain mistakes; the official description above is the record.