# CVE-2006-3747: Integer overflow in n/a

> Remote attackers can crash the Apache web server or potentially execute arbitrary code via crafted URLs when the RewriteEngine is enabled.

- **Severity:** High 7.6 (`AV:N/AC:H/Au:N/C:C/I:C/A:C`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 28 Jul 2006
- **Updated:** 7 Aug 2024
- **Also known as:** DEBIAN-CVE-2006-3747, DSA-1131-1, DSA-1132-1, GHSA-47q7-qpgp-938j

## What is CVE-2006-3747?

CVE-2006-3747 is a high-severity vulnerability in Apache Http Server, published on 28 Jul 2006. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Off-by-one error in the ldap scheme handling in the Rewrite module (mod_rewrite) in Apache 1.3 from 1.3.28, 2.0.46 and other versions before 2.0.59, and 2.2, when RewriteEngine is enabled, allows remote attackers to cause a denial of service (application crash) and possibly execute arbitrary code via crafted URLs that are not properly handled using certain rewrite rules.

Weakness: CWE-189

## Which versions are affected by CVE-2006-3747?

It affects 3 products.


Products: Apache Http Server, Canonical Ubuntu Linux, Debian Debian Linux.

## How do I fix CVE-2006-3747?

Upgrade to a fixed version.

## Is CVE-2006-3747 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2006-3747 exists.

Public exploit code:

- Information about my advisory on CVE-2006-3747 (Apache mod_rewrite LDAP off-by-one buffer overflow).. At the time, it was the first public working exploit :) (github_poc): https://github.com/defensahacker/CVE-2006-3747
- Apache Module mod_rewrite LDAP Protocol Buffer Overflow (metasploit)
- Apache < 1.3.37/2.0.59/2.2.3 mod_rewrite - Remote Overflow (exploitdb)
- Apache mod_rewrite (Windows x86) - Off-by-One Remote Overflow (exploitdb)
- Apache 2.0.58 mod_rewrite (Windows 2003) - Remote Overflow (exploitdb)
- Apache mod_rewrite - LDAP protocol Buffer Overflow (Metasploit) (exploitdb)

## Other vulnerabilities in Apache Http Server

- [CVE-2021-42013](https://insights.sbomify.com/CVE-2021-42013/): Apache HTTP Server Path Traversal (critical 9.8, exploited in the wild)
- [CVE-2024-38475](https://insights.sbomify.com/CVE-2024-38475/): Apache HTTP Server Improper Escaping of Output (critical 9.1, exploited in the wild)
- [CVE-2021-40438](https://insights.sbomify.com/CVE-2021-40438/): Apache HTTP Server-Side Request Forgery (SSRF) (critical 9.0, exploited in the wild)
- [CVE-2019-0211](https://insights.sbomify.com/CVE-2019-0211/): Apache HTTP Server Privilege Escalation (high 7.8, exploited in the wild)
- [CVE-2021-41773](https://insights.sbomify.com/CVE-2021-41773/): Apache HTTP Server Path Traversal (high 7.5, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2006-3747 and fix it if it is affected.

What it is: CVE-2006-3747 is a high-severity vulnerability in Apache Http Server, published on 28 Jul 2006. 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-2006-3747 exists.

Affected product: Apache Http Server. 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-2006-3747/ (Markdown: https://insights.sbomify.com/CVE-2006-3747/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2006-3747
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2006-3747
- OSV: https://osv.dev/vulnerability/CVE-2006-3747

---
From sbomify Insights: https://insights.sbomify.com/CVE-2006-3747/
Summaries are generated and may contain mistakes; the official description above is the record.