# CVE-2022-3855: 404 to Start <= 1.6.1 - Admin+ Stored XSS

> Admin users can inject malicious scripts via plugin settings, leading to stored XSS in multisite environments.

- **Severity:** Medium 4.8 (`CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 9 Jan 2023
- **Updated:** 9 Apr 2025
- **Also known as:** GHSA-4r7f-wp49-4mv2

## What is CVE-2022-3855?

CVE-2022-3855 is a medium-severity cross-site scripting vulnerability in Unknown 404 to Start, published on 9 Jan 2023. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.

### Official description

The 404 to Start WordPress plugin through 1.6.1 does not sanitise and escape some of its settings, which could allow high privilege users such as admin to perform Stored Cross-Site Scripting attacks even when the unfiltered_html capability is disallowed (for example in multisite setup).

## Which versions are affected by CVE-2022-3855?

It affects 1 product.


Products: 404 to Start Project 404 to Start.

## How do I fix CVE-2022-3855?

No fix has been published for CVE-2022-3855 yet. Limit exposure of the affected software until one is available.

## Is CVE-2022-3855 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2022-3855 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-3855 and fix it if it is affected.

What it is: CVE-2022-3855 is a medium-severity cross-site scripting vulnerability in Unknown 404 to Start, published on 9 Jan 2023. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2022-3855 exists.

Affected product: Unknown 404 to Start. 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-2022-3855/ (Markdown: https://insights.sbomify.com/CVE-2022-3855/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-3855
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-3855
- OSV: https://osv.dev/vulnerability/CVE-2022-3855

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-3855/
Summaries are generated and may contain mistakes; the official description above is the record.