# CVE-2023-33237: Authentication Bypass Without Administrator Privilege

> Attackers can bypass authentication to execute restricted actions on Moxa TN-5900 switches, leading to privilege escalation.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 17 Aug 2023
- **Updated:** 28 Oct 2024
- **Also known as:** GHSA-p33g-779c-ccmq

## What is CVE-2023-33237?

CVE-2023-33237 is a high-severity authentication bypass vulnerability in Moxa TN-5900 Series, published on 17 Aug 2023. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

TN-5900 Series firmware version v3.3 and prior is vulnerable to improper-authentication vulnerability. This vulnerability arises from inadequate authentication measures implemented in the web API handler, allowing low-privileged APIs to execute restricted actions that only high-privileged APIs are allowed This presents a potential risk of unauthorized exploitation by malicious actors.

Weakness: CWE-287 (Improper Authentication), CWE-863 (Incorrect Authorization)

## Which versions are affected by CVE-2023-33237?

It affects 1 product.


Products: Moxa Tn-5900 Firmware.

## How do I fix CVE-2023-33237?

No fix has been published for CVE-2023-33237 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-33237 being exploited?

There is no known exploitation of CVE-2023-33237 in the wild and no public exploit code.

## Other vulnerabilities in Moxa TN-5900 Series

- [CVE-2021-46560](https://insights.sbomify.com/CVE-2021-46560/): Command injection in n/a (critical 9.8)
- [CVE-2023-34213](https://insights.sbomify.com/CVE-2023-34213/): Second Order Command-injection Vulnerability in the Key-generation Function (high 8.8)
- [CVE-2021-46559](https://insights.sbomify.com/CVE-2021-46559/): Weak cryptography in n/a (high 7.5)
- [CVE-2023-34215](https://insights.sbomify.com/CVE-2023-34215/): Second Order Command-injection Vulnerability in the Certificate-generation Function (high 7.2)
- [CVE-2023-3336](https://insights.sbomify.com/CVE-2023-3336/): TN-5900 Series User Enumeration Vulnerability (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-33237 and fix it if it is affected.

What it is: CVE-2023-33237 is a high-severity authentication bypass vulnerability in Moxa TN-5900 Series, published on 17 Aug 2023. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2023-33237 in the wild and no public exploit code.

Affected product: Moxa TN-5900 Series. 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-2023-33237/ (Markdown: https://insights.sbomify.com/CVE-2023-33237/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-33237
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-33237
- OSV: https://osv.dev/vulnerability/CVE-2023-33237

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-33237/
Summaries are generated and may contain mistakes; the official description above is the record.