# CVE-2005-0337: Security feature bypass in n/a

> Remote attackers can bypass email restrictions and relay mail via IPv6 hostnames when specific non-default configurations are enabled.

- **Severity:** High 7.5 (`AV:N/AC:L/Au:N/C:P/I:P/A:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 10 Feb 2005
- **Updated:** 7 Aug 2024
- **Also known as:** DEBIAN-CVE-2005-0337, GHSA-5rxq-6r3q-5xj6, RHSA-2005:152

## What is CVE-2005-0337?

CVE-2005-0337 is a high-severity vulnerability in Redhat Enterprise Linux, published on 10 Feb 2005. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Postfix 2.1.3, when /proc/net/if_inet6 is not available and permit_mx_backup is enabled in smtpd_recipient_restrictions, allows remote attackers to bypass e-mail restrictions and perform mail relaying by sending mail to an IPv6 hostname.

## Which versions are affected by CVE-2005-0337?

It affects 4 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `postfix` | Red Hat:enterprise_linux:4::as | All versions | 2:2.1.5-4.2.RHEL4 |
| `postfix-debuginfo` | Red Hat:enterprise_linux:4::as | All versions | 2:2.1.5-4.2.RHEL4 |
| `postfix-pflogsumm` | Red Hat:enterprise_linux:4::as | All versions | 2:2.1.5-4.2.RHEL4 |
| `postfix` | Red Hat:enterprise_linux:4::desktop | All versions | 2:2.1.5-4.2.RHEL4 |
| `postfix-debuginfo` | Red Hat:enterprise_linux:4::desktop | All versions | 2:2.1.5-4.2.RHEL4 |
| `postfix-pflogsumm` | Red Hat:enterprise_linux:4::desktop | All versions | 2:2.1.5-4.2.RHEL4 |
| `postfix` | Red Hat:enterprise_linux:4::es | All versions | 2:2.1.5-4.2.RHEL4 |
| `postfix-debuginfo` | Red Hat:enterprise_linux:4::es | All versions | 2:2.1.5-4.2.RHEL4 |
| `postfix-pflogsumm` | Red Hat:enterprise_linux:4::es | All versions | 2:2.1.5-4.2.RHEL4 |
| `postfix` | Red Hat:enterprise_linux:4::ws | All versions | 2:2.1.5-4.2.RHEL4 |
| `postfix-debuginfo` | Red Hat:enterprise_linux:4::ws | All versions | 2:2.1.5-4.2.RHEL4 |
| `postfix-pflogsumm` | Red Hat:enterprise_linux:4::ws | All versions | 2:2.1.5-4.2.RHEL4 |

Products: Redhat Enterprise Linux, Redhat Enterprise Linux Desktop, Suse Suse Linux, Wietse Venema Postfix.

## How do I fix CVE-2005-0337?

Apply the vendor's patch.

## Is CVE-2005-0337 being exploited?

There is no known exploitation of CVE-2005-0337 in the wild and no public exploit code.

## Other vulnerabilities in Redhat Enterprise Linux

- [CVE-2018-14667](https://insights.sbomify.com/CVE-2018-14667/): Red Hat JBoss RichFaces Framework Expression Language Injection (critical 9.8, exploited in the wild)
- [CVE-2021-20325](https://insights.sbomify.com/CVE-2021-20325/): Missing fixes for CVE-2021-40438 and CVE-2021-26691 in the versions of httpd, as shipped in Red Hat Enterprise Linux 8.5.0, causes a securit (critical 9.8)
- [CVE-2018-25011](https://insights.sbomify.com/CVE-2018-25011/): Memory corruption in libwebp (critical 9.8)
- [CVE-2018-25014](https://insights.sbomify.com/CVE-2018-25014/): Other in libwebp (critical 9.8)
- [CVE-2014-3585](https://insights.sbomify.com/CVE-2014-3585/): Supply chain in redhat-upgrade-tool (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2005-0337 and fix it if it is affected.

What it is: CVE-2005-0337 is a high-severity vulnerability in Redhat Enterprise Linux, published on 10 Feb 2005. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2005-0337 in the wild and no public exploit code.

Affected product: Redhat Enterprise Linux. 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-2005-0337/ (Markdown: https://insights.sbomify.com/CVE-2005-0337/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2005-0337
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2005-0337
- OSV: https://osv.dev/vulnerability/CVE-2005-0337

---
From sbomify Insights: https://insights.sbomify.com/CVE-2005-0337/
Summaries are generated and may contain mistakes; the official description above is the record.