# CVE-2018-21206: Memory corruption in n/a

> Unauthenticated attackers can trigger a stack-based buffer overflow in various NETGEAR routers to execute arbitrary code.

- **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-j59j-93jf-69cc

## What is CVE-2018-21206?

CVE-2018-21206 is a high-severity memory corruption vulnerability in Netgear D7800 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 a stack-based buffer overflow by an unauthenticated attacker. This affects D7800 before 1.0.1.30, EX2700 before 1.0.1.28, R6100 before 1.0.1.20, R7500 before 1.0.0.118, R7500v2 before 1.0.3.24, R7800 before 1.0.2.40, R9000 before 1.0.2.52, WN2000RPTv3 before 1.0.1.20, WN3000RPv3 before 1.0.2.50, WN3100RPv2 before 1.0.0.56, WNDR3700v4 before 1.0.2.96, WNDR4300 before 1.0.2.98, WNDR4300v2 before 1.0.0.50, and WNDR4500v3 before 1.0.0.50.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2018-21206?

It affects 12 products.


Products: Netgear D7800 Firmware, Netgear Ex2700 Firmware, Netgear R6100 Firmware, Netgear R7500 Firmware, Netgear R7800 Firmware, Netgear R900 Firmware, Netgear Wn2000rpt Firmware, Netgear Wn3000rp Firmware, Netgear Wn3100rp Firmware, Netgear Wndr3700 Firmware, Netgear Wndr4300 Firmware, Netgear Wndr4500 Firmware.

## How do I fix CVE-2018-21206?

No fix has been published for CVE-2018-21206 yet. Limit exposure of the affected software until one is available.

## Is CVE-2018-21206 being exploited?

There is no known exploitation of CVE-2018-21206 in the wild and no public exploit code.

## Other vulnerabilities in Netgear D7800 Firmware

- [CVE-2021-45618](https://insights.sbomify.com/CVE-2021-45618/): Command injection in n/a (critical 9.6)
- [CVE-2021-34947](https://insights.sbomify.com/CVE-2021-34947/): NETGEAR R7800 net-cgi Out-Of-Bounds Write Remote Code Execution Vulnerability (high 8.8)
- [CVE-2022-27641](https://insights.sbomify.com/CVE-2022-27641/): Integer overflow in R6700v3 (high 8.8)
- [CVE-2020-26909](https://insights.sbomify.com/CVE-2020-26909/): Command injection in n/a (high 8.8)
- [CVE-2018-21202](https://insights.sbomify.com/CVE-2018-21202/): Memory corruption in n/a (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-21206 and fix it if it is affected.

What it is: CVE-2018-21206 is a high-severity memory corruption vulnerability in Netgear D7800 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-2018-21206 in the wild and no public exploit code.

Affected product: Netgear D7800 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-2018-21206/ (Markdown: https://insights.sbomify.com/CVE-2018-21206/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-21206
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-21206
- OSV: https://osv.dev/vulnerability/CVE-2018-21206

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-21206/
Summaries are generated and may contain mistakes; the official description above is the record.