# CVE-2009-2904: Privilege escalation in n/a

> Local users can escalate privileges by exploiting hard links to setuid programs within a chroot directory in OpenSSH.

- **Severity:** Medium 6.9 (`AV:L/AC:M/Au:N/C:C/I:C/A:C`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 1 Oct 2009
- **Updated:** 7 Aug 2024
- **Also known as:** GHSA-73m8-jfrm-fr4j, RHSA-2009:1470

## What is CVE-2009-2904?

CVE-2009-2904 is a medium-severity vulnerability in OpenSSH, published on 1 Oct 2009. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A certain Red Hat modification to the ChrootDirectory feature in OpenSSH 4.8, as used in sshd in OpenSSH 4.3 in Red Hat Enterprise Linux (RHEL) 5.4 and Fedora 11, allows local users to gain privileges via hard links to setuid programs that use configuration files within the chroot directory, related to requirements for directory ownership.

Weakness: CWE-16

## Which versions are affected by CVE-2009-2904?

It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `openssh` | Red Hat:enterprise_linux:5::client | All versions | 0:4.3p2-36.el5_4.2 |
| `openssh-askpass` | Red Hat:enterprise_linux:5::client | All versions | 0:4.3p2-36.el5_4.2 |
| `openssh-clients` | Red Hat:enterprise_linux:5::client | All versions | 0:4.3p2-36.el5_4.2 |
| `openssh-debuginfo` | Red Hat:enterprise_linux:5::client | All versions | 0:4.3p2-36.el5_4.2 |
| `openssh-server` | Red Hat:enterprise_linux:5::client | All versions | 0:4.3p2-36.el5_4.2 |
| `openssh` | Red Hat:enterprise_linux:5::server | All versions | 0:4.3p2-36.el5_4.2 |
| `openssh-askpass` | Red Hat:enterprise_linux:5::server | All versions | 0:4.3p2-36.el5_4.2 |
| `openssh-clients` | Red Hat:enterprise_linux:5::server | All versions | 0:4.3p2-36.el5_4.2 |
| `openssh-debuginfo` | Red Hat:enterprise_linux:5::server | All versions | 0:4.3p2-36.el5_4.2 |
| `openssh-server` | Red Hat:enterprise_linux:5::server | All versions | 0:4.3p2-36.el5_4.2 |

Products: OpenSSH.

## How do I fix CVE-2009-2904?

Apply the vendor's patch.

## Is CVE-2009-2904 being exploited?

There is no known exploitation of CVE-2009-2904 in the wild and no public exploit code.

## Other vulnerabilities in OpenSSH

- [CVE-2003-0786](https://insights.sbomify.com/CVE-2003-0786/): Auth bypass in n/a (critical 10.0)
- [CVE-2003-0693](https://insights.sbomify.com/CVE-2003-0693/): Memory corruption in n/a (critical 10.0)
- [CVE-2002-0640](https://insights.sbomify.com/CVE-2002-0640/): Memory corruption in n/a (critical 10.0)
- [CVE-2001-0144](https://insights.sbomify.com/CVE-2001-0144/): Integer overflow in n/a (critical 10.0)
- [CVE-2000-0999](https://insights.sbomify.com/CVE-2000-0999/): Memory corruption in n/a (critical 10.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2009-2904 and fix it if it is affected.

What it is: CVE-2009-2904 is a medium-severity vulnerability in OpenSSH, published on 1 Oct 2009. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2009-2904 in the wild and no public exploit code.

Affected product: OpenSSH. 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-2009-2904/ (Markdown: https://insights.sbomify.com/CVE-2009-2904/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2009-2904
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2009-2904
- OSV: https://osv.dev/vulnerability/CVE-2009-2904

---
From sbomify Insights: https://insights.sbomify.com/CVE-2009-2904/
Summaries are generated and may contain mistakes; the official description above is the record.