# CVE-2023-4278: MasterStudy LMS < 3.0.18 - Unauthenticated Instructor Account Creation

> Unauthenticated attackers can register as instructors to create courses and posts due to missing registration checks in the MasterStudy LMS plugin.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 11 Sep 2023
- **Updated:** 23 Apr 2025
- **Also known as:** GHSA-522j-v5mv-h6mw

## What is CVE-2023-4278?

CVE-2023-4278 is a high-severity missing authorization vulnerability in Unknown MasterStudy LMS WordPress Plugin, published on 11 Sep 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The MasterStudy LMS WordPress Plugin WordPress plugin before 3.0.18 does not have proper checks in place during registration allowing anyone to register on the site as an instructor. They can then add courses and/or posts.

## Which versions are affected by CVE-2023-4278?

It affects 1 product.


Products: Stylemixthemes Masterstudy Lms.

## How do I fix CVE-2023-4278?

No fix has been published for CVE-2023-4278 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-4278 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-4278 exists.

Public exploit code:

- Wordpress Plugin Masterstudy LMS <= 3.0.17 - Unauthenticated Instructor Account Creation. (github_poc): https://github.com/revan-ar/CVE-2023-4278
- Wordpress Plugin Masterstudy LMS - 3.0.17 - Unauthenticated Instructor Account Creation (exploitdb)

## Other vulnerabilities in Unknown MasterStudy LMS WordPress Plugin

- [CVE-2024-3136](https://insights.sbomify.com/CVE-2024-3136/): MasterStudy LMS <= 3.3.3 - Unauthenticated Local File Inclusion via template (critical 9.8)
- [CVE-2024-2409](https://insights.sbomify.com/CVE-2024-2409/): MasterStudy LMS <= 3.3.1 - Unauthenticated Privilege Escalation via stm_lms_register AJAX Action (critical 9.8)
- [CVE-2024-2411](https://insights.sbomify.com/CVE-2024-2411/): MasterStudy LMS <= 3.3.0 - Unauthenticated Local File Inclusion via modal (critical 9.8)
- [CVE-2024-1512](https://insights.sbomify.com/CVE-2024-1512/): MasterStudy LMS WordPress Plugin – for Online Courses and Education <= 3.2.5 - Unauthenticated SQL Injection (critical 9.8)
- [CVE-2022-0441](https://insights.sbomify.com/CVE-2022-0441/): MasterStudy LMS < 2.7.6 - Unauthenticated Admin Account Creation (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-4278 and fix it if it is affected.

What it is: CVE-2023-4278 is a high-severity missing authorization vulnerability in Unknown MasterStudy LMS WordPress Plugin, published on 11 Sep 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-4278 exists.

Affected product: Unknown MasterStudy LMS WordPress Plugin. 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-2023-4278/ (Markdown: https://insights.sbomify.com/CVE-2023-4278/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-4278
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-4278
- OSV: https://osv.dev/vulnerability/CVE-2023-4278

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-4278/
Summaries are generated and may contain mistakes; the official description above is the record.