# CVE-2021-40219: Code Injection in Bolt CMS

> An authenticated attacker can inject server-side templates into themes to achieve remote code execution in Bolt CMS.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 11 Apr 2022
- **Updated:** 9 Jul 2026
- **Also known as:** GHSA-gprh-7767-cw39

## What is CVE-2021-40219?

CVE-2021-40219 is a high-severity code injection vulnerability in n/a, published on 11 Apr 2022. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Bolt CMS <= 4.2 is vulnerable to Remote Code Execution. Unsafe theme rendering allows an authenticated attacker to edit theme to inject server-side template injection that leads to remote code execution.

Weakness: CWE-94 (Improper Control of Generation of Code)

## Which versions are affected by CVE-2021-40219?

2 open source packages ship an affected version, including bolt/core. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `bolt/core` | Packagist | All versions to 4.2 | None |
| `bolt/core` | Packagist | All versions to 4.2 | None |

Products: Bolt Bolt Cms.

## How do I fix CVE-2021-40219?

No fix has been published for CVE-2021-40219 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-40219 being exploited?

There is no known exploitation of CVE-2021-40219 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2022-36532](https://insights.sbomify.com/CVE-2022-36532/): File upload in n/a (high 8.8)
- [CVE-2018-19933](https://insights.sbomify.com/CVE-2018-19933/): Bolt Cross-site Scripting (XSS) via text input click preview button (medium 6.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-40219 and fix it if it is affected.

What it is: CVE-2021-40219 is a high-severity code injection vulnerability in n/a, published on 11 Apr 2022. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-40219 in the wild and no public exploit code.

Affected packages and fixed versions:
- bolt/core (Packagist): affected all versions up to 4.2; no fix listed
- bolt/core (Packagist): affected all versions up to 4.2; no fix listed

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-2021-40219/ (Markdown: https://insights.sbomify.com/CVE-2021-40219/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-40219
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-40219
- OSV: https://osv.dev/vulnerability/CVE-2021-40219

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-40219/
Summaries are generated and may contain mistakes; the official description above is the record.