# CVE-2021-22539: Code execution in VSCode-bazel via malicious Bazel config files

> Attackers can execute arbitrary code by placing a malicious JSON config file in the project folder, affecting VSCode Bazel extension users.

- **Severity:** High 8.2 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 16 Apr 2021
- **Updated:** 17 Sep 2024
- **Also known as:** GHSA-2rcw-j8x4-hgcv

## What is CVE-2021-22539?

CVE-2021-22539 is a high-severity code injection vulnerability in Google LLC VSCode-Bazel, published on 16 Apr 2021. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

An attacker can place a crafted JSON config file into the project folder pointing to a custom executable. VScode-bazel allows the workspace path to lint *.bzl files to be set via this config file. As such the attacker is able to execute any executable on the system through vscode-bazel. We recommend upgrading to version 0.4.1 or above.

Weakness: CWE-668 (Exposure of Resource to Wrong Sphere), CWE-73 (External Control of File Name or Path)

## Which versions are affected by CVE-2021-22539?

It affects 1 product.


Products: Google Bazel.

## How do I fix CVE-2021-22539?

No fix has been published for CVE-2021-22539 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-22539 being exploited?

There is no known exploitation of CVE-2021-22539 in the wild and no public exploit code.

## Other vulnerabilities in Google LLC VSCode-Bazel

- [CVE-2022-3474](https://insights.sbomify.com/CVE-2022-3474/): Bazel leaks user credentials through the remote assets API (medium 5.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-22539 and fix it if it is affected.

What it is: CVE-2021-22539 is a high-severity code injection vulnerability in Google LLC VSCode-Bazel, published on 16 Apr 2021. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2021-22539 in the wild and no public exploit code.

Affected product: Google LLC VSCode-Bazel. 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-2021-22539/ (Markdown: https://insights.sbomify.com/CVE-2021-22539/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-22539
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-22539
- OSV: https://osv.dev/vulnerability/CVE-2021-22539

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-22539/
Summaries are generated and may contain mistakes; the official description above is the record.