# CVE-2020-25014: Memory corruption in n/a

> Remote unauthenticated attackers can execute arbitrary code on Zyxel UTM and VPN gateways via a stack-based buffer overflow in the web interface.

- **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:** 27 Nov 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-f57w-r4hj-rw7w

## What is CVE-2020-25014?

CVE-2020-25014 is a critical memory corruption vulnerability in n/a, published on 27 Nov 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A stack-based buffer overflow in fbwifi_continue.cgi on Zyxel UTM and VPN series of gateways running firmware version V4.30 through to V4.55 allows remote unauthenticated attackers to execute arbitrary code via a crafted http packet.

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

## Which versions are affected by CVE-2020-25014?

It affects 2 products.


Products: Zyxel Access Points Firmware, Zyxel Zld.

## How do I fix CVE-2020-25014?

No fix has been published for CVE-2020-25014 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-25014 being exploited?

There is no known exploitation of CVE-2020-25014 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-25014 and fix it if it is affected.

What it is: CVE-2020-25014 is a critical memory corruption vulnerability in n/a, published on 27 Nov 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-2020-25014 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-2020-25014/ (Markdown: https://insights.sbomify.com/CVE-2020-25014/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-25014
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-25014
- OSV: https://osv.dev/vulnerability/CVE-2020-25014

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-25014/
Summaries are generated and may contain mistakes; the official description above is the record.