# CVE-2009-0692: Memory corruption in n/a

> Remote attackers can execute arbitrary code on systems running ISC DHCP client by sending a crafted subnet-mask option from a malicious DHCP server.

- **Severity:** Critical 10.0 (`AV:N/AC:L/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:** 14 Jul 2009
- **Updated:** 7 Aug 2024
- **Also known as:** DSA-1833-1, GHSA-cjw8-pp44-m8v2, RHSA-2009:1136

## What is CVE-2009-0692?

CVE-2009-0692 is a critical memory corruption vulnerability in n/a, published on 14 Jul 2009. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Stack-based buffer overflow in the script_write_params method in client/dhclient.c in ISC DHCP dhclient 4.1 before 4.1.0p1, 4.0 before 4.0.1p1, 3.1 before 3.1.2p1, 3.0, and 2.0 allows remote DHCP servers to execute arbitrary code via a crafted subnet-mask option.

Weakness: CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2009-0692?

It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `dhclient` | Red Hat:enterprise_linux:4::as | All versions | 7:3.0.1-65.el4_8.1 |
| `dhcp` | Red Hat:enterprise_linux:4::as | All versions | 7:3.0.1-65.el4_8.1 |
| `dhcp-debuginfo` | Red Hat:enterprise_linux:4::as | All versions | 7:3.0.1-65.el4_8.1 |
| `dhcp-devel` | Red Hat:enterprise_linux:4::as | All versions | 7:3.0.1-65.el4_8.1 |
| `dhclient` | Red Hat:enterprise_linux:4::desktop | All versions | 7:3.0.1-65.el4_8.1 |
| `dhcp` | Red Hat:enterprise_linux:4::desktop | All versions | 7:3.0.1-65.el4_8.1 |
| `dhcp-debuginfo` | Red Hat:enterprise_linux:4::desktop | All versions | 7:3.0.1-65.el4_8.1 |
| `dhcp-devel` | Red Hat:enterprise_linux:4::desktop | All versions | 7:3.0.1-65.el4_8.1 |
| `dhclient` | Red Hat:enterprise_linux:4::es | All versions | 7:3.0.1-65.el4_8.1 |
| `dhcp` | Red Hat:enterprise_linux:4::es | All versions | 7:3.0.1-65.el4_8.1 |
| `dhcp-debuginfo` | Red Hat:enterprise_linux:4::es | All versions | 7:3.0.1-65.el4_8.1 |
| `dhcp-devel` | Red Hat:enterprise_linux:4::es | All versions | 7:3.0.1-65.el4_8.1 |
| `dhclient` | Red Hat:enterprise_linux:4::ws | All versions | 7:3.0.1-65.el4_8.1 |
| `dhcp` | Red Hat:enterprise_linux:4::ws | All versions | 7:3.0.1-65.el4_8.1 |
| `dhcp-debuginfo` | Red Hat:enterprise_linux:4::ws | All versions | 7:3.0.1-65.el4_8.1 |
| `dhcp-devel` | Red Hat:enterprise_linux:4::ws | All versions | 7:3.0.1-65.el4_8.1 |
| `dhclient` | Red Hat:rhel_eus:4.7::as | All versions | 7:3.0.1-62.el4_7.1 |
| `dhcp` | Red Hat:rhel_eus:4.7::as | All versions | 7:3.0.1-62.el4_7.1 |
| `dhcp-debuginfo` | Red Hat:rhel_eus:4.7::as | All versions | 7:3.0.1-62.el4_7.1 |
| `dhcp-devel` | Red Hat:rhel_eus:4.7::as | All versions | 7:3.0.1-62.el4_7.1 |
| `dhclient` | Red Hat:rhel_eus:4.7::es | All versions | 7:3.0.1-62.el4_7.1 |
| `dhcp` | Red Hat:rhel_eus:4.7::es | All versions | 7:3.0.1-62.el4_7.1 |
| `dhcp-debuginfo` | Red Hat:rhel_eus:4.7::es | All versions | 7:3.0.1-62.el4_7.1 |
| `dhcp-devel` | Red Hat:rhel_eus:4.7::es | All versions | 7:3.0.1-62.el4_7.1 |

Products: Isc Dhcp.

## How do I fix CVE-2009-0692?

Upgrade to a fixed version.

## Is CVE-2009-0692 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2009-0692 exists.

Public exploit code:

- ISC DHCP dhclient < 3.1.2p1 - Remote Buffer Overflow (PoC) (exploitdb)

## Other vulnerabilities in n/a

- [CVE-2011-0413](https://insights.sbomify.com/CVE-2011-0413/): Denial of service in n/a (high 7.8)
- [CVE-2018-5732](https://insights.sbomify.com/CVE-2018-5732/): A specially constructed response from a malicious server can cause a buffer overflow in dhclient (high 7.5)
- [CVE-2009-1893](https://insights.sbomify.com/CVE-2009-1893/): Path traversal in n/a (medium 6.9)
- [CVE-2011-4868](https://insights.sbomify.com/CVE-2011-4868/): Null dereference in n/a (medium 6.1)
- [CVE-2012-3570](https://insights.sbomify.com/CVE-2012-3570/): Memory corruption in n/a (medium 5.7)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2009-0692 and fix it if it is affected.

What it is: CVE-2009-0692 is a critical memory corruption vulnerability in n/a, published on 14 Jul 2009. 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-2009-0692 exists.

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-2009-0692/ (Markdown: https://insights.sbomify.com/CVE-2009-0692/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2009-0692
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2009-0692
- OSV: https://osv.dev/vulnerability/CVE-2009-0692

---
From sbomify Insights: https://insights.sbomify.com/CVE-2009-0692/
Summaries are generated and may contain mistakes; the official description above is the record.