# CVE-2021-43836: PHP file inclusion in the Sulu admin panel

> Attackers can read arbitrary local files and execute remote code via PHP file inclusion in the Sulu admin panel.

- **Severity:** High 8.5 (`CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/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:** Yes
- **Published:** 15 Dec 2021
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-vx6j-pjrh-vgjh

## What is CVE-2021-43836?

CVE-2021-43836 is a high-severity path traversal vulnerability in sulu, published on 15 Dec 2021. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Sulu is an open-source PHP content management system based on the Symfony framework. In affected versions an attacker can read arbitrary local files via a PHP file include. In a default configuration this also leads to remote code execution. The problem is patched with the Versions 1.6.44, 2.2.18, 2.3.8, 2.4.0. For users unable to upgrade overwrite the service `sulu_route.generator.expression_token_provider` and wrap the translator before passing it to the expression language.

Weakness: CWE-22 (Improper Limitation of a Pathname to a Restricted Directory)

## Which versions are affected by CVE-2021-43836?

8 open source packages ship an affected version, including sulu/sulu. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `sulu/sulu` | Packagist | All versions | 1.6.44 |
| `sulu/sulu` | Packagist | All versions | 1.6.44 |
| `sulu/sulu` | Packagist | From 2.0.0 | 2.2.18 |
| `sulu/sulu` | Packagist | From 2.0.0 | 2.2.18 |
| `sulu/sulu` | Packagist | From 2.3.0 | 2.3.8 |
| `sulu/sulu` | Packagist | From 2.3.0 | 2.3.8 |
| `sulu/sulu` | Packagist | From 2.4.0-RC1 | 2.4.0 |
| `sulu/sulu` | Packagist | From 2.4.0-RC1 | 2.4.0 |

Products: Sulu Sulu.

## How do I fix CVE-2021-43836?

Upgrade sulu/sulu to a fixed version for your release line: 1.6.44, 2.2.18, 2.3.8 or 2.4.0.

## Is CVE-2021-43836 being exploited?

There is no known exploitation of CVE-2021-43836 in the wild and no public exploit code.

## Other vulnerabilities in sulu

- [CVE-2021-32737](https://insights.sbomify.com/CVE-2021-32737/): XSS Injection in Media Collection Title was possible (high 8.4)
- [CVE-2021-43835](https://insights.sbomify.com/CVE-2021-43835/): Privilege escalation in the Sulu Admin panel (high 7.2)
- [CVE-2024-27915](https://insights.sbomify.com/CVE-2024-27915/): Sulu grants access to pages regardless of role permissions (medium 6.8)
- [CVE-2021-41169](https://insights.sbomify.com/CVE-2021-41169/): Improper Neutralization HTML tags in sulu/sulu (medium 6.2)
- [CVE-2024-47617](https://insights.sbomify.com/CVE-2024-47617/): Reflected XSS Vulnerability in Sulu Media Bundle (medium 6.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-43836 and fix it if it is affected.

What it is: CVE-2021-43836 is a high-severity path traversal vulnerability in sulu, published on 15 Dec 2021. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-43836 in the wild and no public exploit code.

Affected packages and fixed versions:
- sulu/sulu (Packagist): affected all versions; fixed in 1.6.44
- sulu/sulu (Packagist): affected all versions; fixed in 1.6.44
- sulu/sulu (Packagist): affected from 2.0.0; fixed in 2.2.18
- sulu/sulu (Packagist): affected from 2.0.0; fixed in 2.2.18
- sulu/sulu (Packagist): affected from 2.3.0; fixed in 2.3.8
- sulu/sulu (Packagist): affected from 2.3.0; fixed in 2.3.8
- sulu/sulu (Packagist): affected from 2.4.0-RC1; fixed in 2.4.0
- sulu/sulu (Packagist): affected from 2.4.0-RC1; fixed in 2.4.0

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-2021-43836/ (Markdown: https://insights.sbomify.com/CVE-2021-43836/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-43836
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-43836
- OSV: https://osv.dev/vulnerability/CVE-2021-43836

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-43836/
Summaries are generated and may contain mistakes; the official description above is the record.