# CVE-2009-3943: Denial of service in n/a

> Remote attackers can cause Internet Explorer to hang via a malicious JavaScript loop that manipulates the home page settings.

- **Severity:** Medium 5.0 (`AV:N/AC:L/Au:N/C:N/I:N/A:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 16 Nov 2009
- **Updated:** 7 Aug 2024
- **Also known as:** GHSA-vhjx-q9cm-jppr

## What is CVE-2009-3943?

CVE-2009-3943 is a medium-severity denial of service vulnerability in Microsoft Internet Explorer, published on 16 Nov 2009. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

Microsoft Internet Explorer 6 through 6.0.2900.2180 and 7 through 7.0.6000.16711 allows remote attackers to cause a denial of service (application hang) via a JavaScript loop that configures the home page by using the setHomePage method and a DHTML behavior property.

## Which versions are affected by CVE-2009-3943?

It affects 1 product.


Products: Microsoft Internet Explorer.

## How do I fix CVE-2009-3943?

No fix has been published for CVE-2009-3943 yet. Limit exposure of the affected software until one is available.

## Is CVE-2009-3943 being exploited?

There is no known exploitation of CVE-2009-3943 in the wild and no public exploit code.

## Other vulnerabilities in Microsoft Internet Explorer

- [CVE-2014-1776](https://insights.sbomify.com/CVE-2014-1776/): Microsoft Internet Explorer Memory Corruption (critical 9.8, exploited in the wild)
- [CVE-2021-27085](https://insights.sbomify.com/CVE-2021-27085/): Microsoft Internet Explorer Remote Code Execution (high 8.8, exploited in the wild)
- [CVE-2017-0222](https://insights.sbomify.com/CVE-2017-0222/): Microsoft Internet Explorer Remote Code Execution (high 8.8, exploited in the wild)
- [CVE-2017-0210](https://insights.sbomify.com/CVE-2017-0210/): Microsoft Internet Explorer Privilege Escalation (high 8.8, exploited in the wild)
- [CVE-2017-0149](https://insights.sbomify.com/CVE-2017-0149/): Microsoft Internet Explorer Memory Corruption (high 8.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2009-3943 and fix it if it is affected.

What it is: CVE-2009-3943 is a medium-severity denial of service vulnerability in Microsoft Internet Explorer, published on 16 Nov 2009. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2009-3943 in the wild and no public exploit code.

Affected product: Microsoft Internet Explorer. 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-2009-3943/ (Markdown: https://insights.sbomify.com/CVE-2009-3943/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2009-3943
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2009-3943
- OSV: https://osv.dev/vulnerability/CVE-2009-3943

---
From sbomify Insights: https://insights.sbomify.com/CVE-2009-3943/
Summaries are generated and may contain mistakes; the official description above is the record.