# CVE-2020-13537: Privilege escalation in Moxa

> Local attackers can escalate privileges to SYSTEM by modifying insecure file permissions in Moxa MXView, allowing arbitrary code execution.

- **Severity:** Critical 9.3 (`CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 5 Nov 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-9vx5-p3h2-529c

## What is CVE-2020-13537?

CVE-2020-13537 is a critical vulnerability in Moxa, published on 5 Nov 2020. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

An exploitable local privilege elevation vulnerability exists in the file system permissions of Moxa MXView series 3.1.8 installation. Depending on the vector chosen, an attacker can either add code to a script or replace a binary.By default MXViewService, which starts as a NT SYSTEM authority user executes a series of Node.Js scripts to start additional application functionality and among them the mosquitto executable is also run.

Weakness: CWE-276 (Incorrect Default Permissions)

## Which versions are affected by CVE-2020-13537?

It affects 1 product.


Products: Moxa Mxview.

## How do I fix CVE-2020-13537?

No fix has been published for CVE-2020-13537 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-13537 being exploited?

There is no known exploitation of CVE-2020-13537 in the wild and no public exploit code.

## Other vulnerabilities in Moxa

- [CVE-2021-40390](https://insights.sbomify.com/CVE-2021-40390/): Auth bypass in MXView Series (critical 10.0)
- [CVE-2021-38454](https://insights.sbomify.com/CVE-2021-38454/): Moxa MXview Network Management Software (critical 10.0)
- [CVE-2021-38456](https://insights.sbomify.com/CVE-2021-38456/): Moxa MXview Network Management Software (critical 9.8)
- [CVE-2021-38458](https://insights.sbomify.com/CVE-2021-38458/): Moxa MXview Network Management Software (critical 9.8)
- [CVE-2020-13536](https://insights.sbomify.com/CVE-2020-13536/): Privilege escalation in Moxa (critical 9.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-13537 and fix it if it is affected.

What it is: CVE-2020-13537 is a critical vulnerability in Moxa, published on 5 Nov 2020. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2020-13537 in the wild and no public exploit code.

Affected product: Moxa. 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-2020-13537/ (Markdown: https://insights.sbomify.com/CVE-2020-13537/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-13537
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-13537
- OSV: https://osv.dev/vulnerability/CVE-2020-13537

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-13537/
Summaries are generated and may contain mistakes; the official description above is the record.