# CVE-2009-20009: Belkin Bulldog Plus Web Service Buffer Overflow

> Remote attackers can execute arbitrary code on Belkin Bulldog Plus via a stack-based buffer overflow in the web service authentication handler.

- **Severity:** Critical 9.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 30 Aug 2025
- **Updated:** 15 May 2026
- **Also known as:** GHSA-9gqw-88p3-59j6

## What is CVE-2009-20009?

CVE-2009-20009 is a critical memory corruption vulnerability in Belkin International, Inc. Bulldog Plus UPS Monitoring Software, published on 30 Aug 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Belkin Bulldog Plus version 4.0.2 build 1219 contains a stack-based buffer overflow vulnerability in its web service authentication handler. When a specially crafted HTTP request is sent with an oversized Authorization header, the application fails to properly validate the input length before copying it into a fixed-size buffer, resulting in memory corruption and potential remote code execution. Exploitation requires network access and does not require prior authentication.

Weakness: CWE-121 (Stack-based Buffer Overflow)

## Which versions are affected by CVE-2009-20009?


## How do I fix CVE-2009-20009?

No fix has been published for CVE-2009-20009 yet. Limit exposure of the affected software until one is available.

## Is CVE-2009-20009 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2009-20009 exists.

Public exploit code:

- Belkin Bulldog Plus Web Service Buffer Overflow (metasploit)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2009-20009 and fix it if it is affected.

What it is: CVE-2009-20009 is a critical memory corruption vulnerability in Belkin International, Inc. Bulldog Plus UPS Monitoring Software, published on 30 Aug 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2009-20009 exists.

Affected product: Belkin International, Inc. Bulldog Plus UPS Monitoring Software. 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-2009-20009/ (Markdown: https://insights.sbomify.com/CVE-2009-20009/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2009-20009
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2009-20009
- OSV: https://osv.dev/vulnerability/CVE-2009-20009

---
From sbomify Insights: https://insights.sbomify.com/CVE-2009-20009/
Summaries are generated and may contain mistakes; the official description above is the record.