# CVE-2025-4140: Netgear EX6120 sub_30394 buffer overflow

> Remote attackers can trigger a buffer overflow in the Netgear EX6120 via the host argument, potentially leading to code execution.

- **Severity:** High 8.7 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 30 Apr 2025
- **Updated:** 2 May 2025
- **Also known as:** GHSA-mf3m-m2fx-pq76

## What is CVE-2025-4140?

CVE-2025-4140 is a high-severity memory corruption vulnerability in Netgear EX6120, published on 30 Apr 2025. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A vulnerability, which was classified as critical, has been found in Netgear EX6120 1.0.3.94. Affected by this issue is the function sub_30394. The manipulation of the argument host leads to buffer overflow. The attack may be launched remotely. The vendor was contacted early about this disclosure but did not respond in any way.

Weakness: CWE-120 (Buffer Copy without Checking Size of Input), CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2025-4140?

It affects 1 product.


Products: Netgear Ex6120 Firmware.

## How do I fix CVE-2025-4140?

No fix has been published for CVE-2025-4140 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-4140 being exploited?

There is no known exploitation of CVE-2025-4140 in the wild and no public exploit code.

## Other vulnerabilities in Netgear EX6120

- [CVE-2025-4139](https://insights.sbomify.com/CVE-2025-4139/): Netgear EX6120 fwAcosCgiInbound buffer overflow (high 8.7)
- [CVE-2024-35518](https://insights.sbomify.com/CVE-2024-35518/): Command injection in n/a (high 8.4)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-4140 and fix it if it is affected.

What it is: CVE-2025-4140 is a high-severity memory corruption vulnerability in Netgear EX6120, published on 30 Apr 2025. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-4140 in the wild and no public exploit code.

Affected product: Netgear EX6120. 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-2025-4140/ (Markdown: https://insights.sbomify.com/CVE-2025-4140/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-4140
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-4140
- OSV: https://osv.dev/vulnerability/CVE-2025-4140

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-4140/
Summaries are generated and may contain mistakes; the official description above is the record.