# CVE-2018-21208: Command injection in n/a

> Unauthenticated attackers can execute arbitrary commands on vulnerable NETGEAR routers via command injection flaws.

- **Severity:** High 8.8 (`CVSS:3.0/AC:L/AV:A/A:H/C:H/I:H/PR:N/S:U/UI:N`)
- **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:** 28 Apr 2020
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-mxgp-249m-rh92

## What is CVE-2018-21208?

CVE-2018-21208 is a high-severity command injection vulnerability in Netgear D6100 Firmware, published on 28 Apr 2020. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Certain NETGEAR devices are affected by command injection by an unauthenticated attacker. This affects D6100 before 1.0.0.57, R6100 before 1.0.1.20, R7500v2 before 1.0.3.24, WNDR4300v2 before 1.0.0.50, and WNDR4500v3 before 1.0.0.50.

Weakness: CWE-74 (Improper Neutralization of Special Elements in Output Used by a Downstream Component)

## Which versions are affected by CVE-2018-21208?

It affects 5 products.


Products: Netgear D6100 Firmware, Netgear R6100 Firmware, Netgear R7500 Firmware, Netgear Wndr4300 Firmware, Netgear Wndr4500 Firmware.

## How do I fix CVE-2018-21208?

No fix has been published for CVE-2018-21208 yet. Limit exposure of the affected software until one is available.

## Is CVE-2018-21208 being exploited?

There is no known exploitation of CVE-2018-21208 in the wild and no public exploit code.

## Other vulnerabilities in Netgear D6100 Firmware

- [CVE-2016-10174](https://insights.sbomify.com/CVE-2016-10174/): NETGEAR WNR2000v5 Router Buffer Overflow (critical 9.8, exploited in the wild)
- [CVE-2017-18764](https://insights.sbomify.com/CVE-2017-18764/): Command injection in n/a (high 8.8)
- [CVE-2018-21113](https://insights.sbomify.com/CVE-2018-21113/): Command injection in n/a (high 8.8)
- [CVE-2017-18776](https://insights.sbomify.com/CVE-2017-18776/): Auth bypass in n/a (high 8.4)
- [CVE-2017-18792](https://insights.sbomify.com/CVE-2017-18792/): Command injection in n/a (high 8.4)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-21208 and fix it if it is affected.

What it is: CVE-2018-21208 is a high-severity command injection vulnerability in Netgear D6100 Firmware, published on 28 Apr 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-2018-21208 in the wild and no public exploit code.

Affected product: Netgear D6100 Firmware. 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-2018-21208/ (Markdown: https://insights.sbomify.com/CVE-2018-21208/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-21208
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-21208
- OSV: https://osv.dev/vulnerability/CVE-2018-21208

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-21208/
Summaries are generated and may contain mistakes; the official description above is the record.