# CVE-2021-36581: File upload in n/a

> Attackers can upload malicious files, such as ASPX scripts, to the Kooboo CMS server due to missing extension validation, leading to remote code execution.

- **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:** 14 Sep 2021
- **Updated:** 9 Jul 2026
- **Also known as:** GHSA-xhhh-8cg4-rhc7

## What is CVE-2021-36581?

CVE-2021-36581 is a critical vulnerability in n/a, published on 14 Sep 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Kooboo CMS 2.1.1.0 is vulnerable to Insecure file upload. It is possible to upload any file extension to the server. The server does not verify the extension of the file and the tester was able to upload an aspx to the server.

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

## Which versions are affected by CVE-2021-36581?

It affects 1 product.


Products: Kooboo Kooboo Cms.

## How do I fix CVE-2021-36581?

No fix has been published for CVE-2021-36581 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-36581 being exploited?

There is no known exploitation of CVE-2021-36581 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2021-36582](https://insights.sbomify.com/CVE-2021-36582/): File upload in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-36581 and fix it if it is affected.

What it is: CVE-2021-36581 is a critical vulnerability in n/a, published on 14 Sep 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-2021-36581 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-2021-36581/ (Markdown: https://insights.sbomify.com/CVE-2021-36581/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-36581
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-36581
- OSV: https://osv.dev/vulnerability/CVE-2021-36581

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-36581/
Summaries are generated and may contain mistakes; the official description above is the record.