# CVE-2021-34982: NETGEAR Multiple Routers httpd Stack-based Buffer Overflow Remote Code Execution Vulnerability

> Network-adjacent attackers can execute arbitrary code as root on NETGEAR routers via a stack-based buffer overflow in the httpd service.

- **Severity:** High 8.8 (`CVSS:3.0/AV:A/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:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 7 May 2024
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-3g79-p8hq-4qgp

## What is CVE-2021-34982?

CVE-2021-34982 is a high-severity memory corruption vulnerability in Netgear D6220 Firmware, published on 7 May 2024. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

NETGEAR Multiple Routers httpd Stack-based Buffer Overflow Remote Code Execution Vulnerability. This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of multiple NETGEAR routers. Authentication is not required to exploit this vulnerability.

The specific flaw exists within the httpd service, which listens on TCP port 80 by default. When parsing the strings file, the process does not properly validate the length of user-supplied data prior to copying it to a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of root.

. Was ZDI-CAN-13709.

Weakness: CWE-787 (Out-of-bounds Write), CWE-121 (Stack-based Buffer Overflow)

## Which versions are affected by CVE-2021-34982?

It affects 52 products.


Products: Netgear D6220 Firmware, Netgear D6400 Firmware, Netgear D7000v2 Firmware, Netgear Dc112a Firmware, Netgear Dgn2200v4 Firmware, Netgear Ex3700 Firmware, Netgear Ex3800 Firmware, Netgear Ex6120 Firmware, Netgear Ex6130 Firmware, Netgear Ex7000 Firmware, Netgear Ex7500 Firmware, Netgear Lax20 Firmware, Netgear Mr60 Firmware, Netgear Mr80 Firmware, Netgear Ms60 Firmware, Netgear Ms80 Firmware, Netgear R6400 Firmware, Netgear R6400v2 Firmware, Netgear R6700v3 Firmware, Netgear R6900p Firmware and 32 more.

## How do I fix CVE-2021-34982?

No fix has been published for CVE-2021-34982 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-34982 being exploited?

There is no known exploitation of CVE-2021-34982 in the wild and no public exploit code.

## Other vulnerabilities in Netgear D6220 Firmware

- [CVE-2016-6277](https://insights.sbomify.com/CVE-2016-6277/): NETGEAR Multiple Routers Remote Code Execution (high 8.8, exploited in the wild)
- [CVE-2021-45527](https://insights.sbomify.com/CVE-2021-45527/): Memory corruption in n/a (critical 9.6)
- [CVE-2021-45610](https://insights.sbomify.com/CVE-2021-45610/): Memory corruption in n/a (critical 9.6)
- [CVE-2021-45638](https://insights.sbomify.com/CVE-2021-45638/): Memory corruption in n/a (critical 9.6)
- [CVE-2023-33533](https://insights.sbomify.com/CVE-2023-33533/): Command injection in n/a (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-34982 and fix it if it is affected.

What it is: CVE-2021-34982 is a high-severity memory corruption vulnerability in Netgear D6220 Firmware, published on 7 May 2024. 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-2021-34982 in the wild and no public exploit code.

Affected product: Netgear D6220 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-2021-34982/ (Markdown: https://insights.sbomify.com/CVE-2021-34982/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-34982
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-34982
- OSV: https://osv.dev/vulnerability/CVE-2021-34982

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From sbomify Insights: https://insights.sbomify.com/CVE-2021-34982/
Summaries are generated and may contain mistakes; the official description above is the record.