# CVE-2018-20334: Command injection in n/a

> Attackers can execute arbitrary commands on ASUS routers via shell metacharacters in the fb_email parameter, gaining full control.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 20 Mar 2020
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-xgrv-mpr3-8pg9

## What is CVE-2018-20334?

CVE-2018-20334 is a critical command injection vulnerability in n/a, published on 20 Mar 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

An issue was discovered in ASUSWRT 3.0.0.4.384.20308. When processing the /start_apply.htm POST data, there is a command injection issue via shell metacharacters in the fb_email parameter. By using this issue, an attacker can control the router and get shell.

Weakness: CWE-78 (Improper Neutralization of Special Elements used in an OS Command)

## Which versions are affected by CVE-2018-20334?

It affects 1 product.


Products: Asus Asuswrt.

## How do I fix CVE-2018-20334?

No fix has been published for CVE-2018-20334 yet. Limit exposure of the affected software until one is available.

## Is CVE-2018-20334 being exploited?

There is no known exploitation of CVE-2018-20334 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2018-5999](https://insights.sbomify.com/CVE-2018-5999/): Auth bypass in n/a (critical 9.8)
- [CVE-2018-6000](https://insights.sbomify.com/CVE-2018-6000/): Missing authorization in n/a (critical 9.8)
- [CVE-2017-15655](https://insights.sbomify.com/CVE-2017-15655/): Memory corruption in n/a (critical 9.6)
- [CVE-2017-15653](https://insights.sbomify.com/CVE-2017-15653/): Auth bypass in n/a (high 8.8)
- [CVE-2017-15656](https://insights.sbomify.com/CVE-2017-15656/): Hardcoded credentials in n/a (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-20334 and fix it if it is affected.

What it is: CVE-2018-20334 is a critical command injection vulnerability in n/a, published on 20 Mar 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2018-20334 in the wild and no public exploit code.

Affected product: n/a. 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-2018-20334/ (Markdown: https://insights.sbomify.com/CVE-2018-20334/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-20334
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-20334
- OSV: https://osv.dev/vulnerability/CVE-2018-20334

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-20334/
Summaries are generated and may contain mistakes; the official description above is the record.