# CVE-2020-12471: Deserialization in n/a

> Remote attackers can execute arbitrary code via unsafe deserialization in MonoX CMS upload handlers.

- **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:** 29 Apr 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-f842-vw35-9x42

## What is CVE-2020-12471?

CVE-2020-12471 is a critical unsafe deserialization vulnerability in n/a, published on 29 Apr 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

MonoX through 5.1.40.5152 allows remote code execution via HTML5Upload.ashx or Pages/SocialNetworking/lng/en-US/PhotoGallery.aspx because of deserialization in ModuleGallery.HTML5Upload, ModuleGallery.SilverLightUploadModule, HTML5Upload, and SilverLightUploadHandler.

Weakness: CWE-502 (Deserialization of Untrusted Data)

## Which versions are affected by CVE-2020-12471?

It affects 1 product.


Products: Mono Monox.

## How do I fix CVE-2020-12471?

No fix has been published for CVE-2020-12471 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-12471 being exploited?

There is no known exploitation of CVE-2020-12471 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2020-12470](https://insights.sbomify.com/CVE-2020-12470/): Code injection in n/a (high 7.2)
- [CVE-2020-12473](https://insights.sbomify.com/CVE-2020-12473/): Command injection in n/a (high 7.2)
- [CVE-2020-12472](https://insights.sbomify.com/CVE-2020-12472/): Cross-site scripting in n/a (medium 5.4)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-12471 and fix it if it is affected.

What it is: CVE-2020-12471 is a critical unsafe deserialization vulnerability in n/a, published on 29 Apr 2020. 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-2020-12471 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-2020-12471/ (Markdown: https://insights.sbomify.com/CVE-2020-12471/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-12471
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-12471
- OSV: https://osv.dev/vulnerability/CVE-2020-12471

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-12471/
Summaries are generated and may contain mistakes; the official description above is the record.