# CVE-2023-40203: WordPress MailChimp Forms by MailMunch plugin <= 3.1.4 - Broken Access Control

> Attackers can bypass access controls in the MailChimp Forms by MailMunch WordPress plugin to perform unauthorized actions.

- **Severity:** Medium 4.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 13 Dec 2024
- **Updated:** 28 Apr 2026
- **Also known as:** GHSA-476h-737f-mc4w

## What is CVE-2023-40203?

CVE-2023-40203 is a medium-severity missing authorization vulnerability in MailChimp Forms by MailMunch, published on 13 Dec 2024. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

Missing Authorization vulnerability in MailMunch MailChimp Forms by MailMunch allows Exploiting Incorrectly Configured Access Control Security Levels.This issue affects MailChimp Forms by MailMunch: from n/a through 3.1.4.

Weakness: CWE-862 (Missing Authorization)

## Which versions are affected by CVE-2023-40203?

It affects 1 product.


Products: Mailmunch Mailchimp Forms.

## How do I fix CVE-2023-40203?

No fix has been published for CVE-2023-40203 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-40203 being exploited?

There is no known exploitation of CVE-2023-40203 in the wild and no public exploit code.

## Other vulnerabilities in MailChimp Forms by MailMunch

- [CVE-2024-29793](https://insights.sbomify.com/CVE-2024-29793/): WordPress MailChimp Forms by MailMunch plugin <= 3.2.2 - Cross Site Scripting (XSS) vulnerability (medium 6.5)
- [CVE-2024-8726](https://insights.sbomify.com/CVE-2024-8726/): MailChimp Forms by MailMunch <= 3.2.3 - Reflected Cross-Site Scripting (medium 6.1)
- [CVE-2024-31378](https://insights.sbomify.com/CVE-2024-31378/): WordPress MailChimp Forms by MailMunch plugin <= 3.2.1 - Cross Site Request Forgery (CSRF) vulnerability (medium 5.4)
- [CVE-2023-45748](https://insights.sbomify.com/CVE-2023-45748/): WordPress MailChimp Forms by MailMunch Plugin <= 3.1.4 is vulnerable to Cross Site Request Forgery (CSRF) (medium 4.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-40203 and fix it if it is affected.

What it is: CVE-2023-40203 is a medium-severity missing authorization vulnerability in MailChimp Forms by MailMunch, published on 13 Dec 2024. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2023-40203 in the wild and no public exploit code.

Affected product: MailChimp Forms by MailMunch. 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-2023-40203/ (Markdown: https://insights.sbomify.com/CVE-2023-40203/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-40203
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-40203
- OSV: https://osv.dev/vulnerability/CVE-2023-40203

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-40203/
Summaries are generated and may contain mistakes; the official description above is the record.