# CVE-2021-42669: File upload in n/a

> Attackers can upload malicious PHP files via the avatar feature to execute arbitrary commands on the web server.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 5 Nov 2021
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-h6f4-pv83-7533

## What is CVE-2021-42669?

CVE-2021-42669 is a critical vulnerability in n/a, published on 5 Nov 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A file upload vulnerability exists in Sourcecodester Engineers Online Portal in PHP via dashboard_teacher.php, which allows changing the avatar through teacher_avatar.php. Once an avatar gets uploaded it is getting uploaded to the /admin/uploads/ directory, and is accessible by all users. By uploading a php webshell containing "<?php system($_GET["cmd"]); ?>" the attacker can execute commands on the web server with - /admin/uploads/php-webshell?cmd=id.

Weakness: CWE-434 (Unrestricted Upload of File with Dangerous Type)

## Which versions are affected by CVE-2021-42669?

It affects 1 product.


Products: Engineers Online Portal Project Engineers Online Portal.

## How do I fix CVE-2021-42669?

No fix has been published for CVE-2021-42669 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-42669 being exploited?

There is no known exploitation of CVE-2021-42669 in the wild and no public exploit code.

Public exploit code:

- CVE-2021-42669 - Remote code execution via unrestricted file upload vulnerability in the Engineers online portal system. (github_poc): https://github.com/0xDeku/CVE-2021-42669

## Other vulnerabilities in n/a

- [CVE-2021-42665](https://insights.sbomify.com/CVE-2021-42665/): SQL injection in n/a (critical 9.8)
- [CVE-2021-42668](https://insights.sbomify.com/CVE-2021-42668/): SQL injection in n/a (critical 9.8)
- [CVE-2021-42670](https://insights.sbomify.com/CVE-2021-42670/): SQL injection in n/a (critical 9.8)
- [CVE-2021-43437](https://insights.sbomify.com/CVE-2021-43437/): Other in n/a (high 8.8)
- [CVE-2021-42666](https://insights.sbomify.com/CVE-2021-42666/): SQL injection in n/a (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-42669 and fix it if it is affected.

What it is: CVE-2021-42669 is a critical vulnerability in n/a, published on 5 Nov 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-42669 in the wild and no public exploit code.

Affected product: n/a. 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-2021-42669/ (Markdown: https://insights.sbomify.com/CVE-2021-42669/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-42669
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-42669
- OSV: https://osv.dev/vulnerability/CVE-2021-42669

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-42669/
Summaries are generated and may contain mistakes; the official description above is the record.