# CVE-2018-0684: Memory corruption in Denbun by NEOJAPAN Inc. (Denbun POP version V3.3P R3.0 and earlier, Denbun IMAP version V3.3I R3.0 and earlier)

> Remote attackers can execute arbitrary code or cause denial of service via crafted multipart/form-data in Denbun mail servers.

- **Severity:** Critical 9.8 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 15 Nov 2018
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-hxr6-gvvg-37vq

## What is CVE-2018-0684?

CVE-2018-0684 is a critical memory corruption vulnerability in Denbun by NEOJAPAN Inc. (Denbun POP version V3.3P R3.0 and earlier, Denbun IMAP version V3.3I R3.0 and earlier), published on 15 Nov 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Buffer overflow in Denbun by NEOJAPAN Inc. (Denbun POP version V3.3P R3.0 and earlier, Denbun IMAP version V3.3I R3.0 and earlier) allows remote attackers to execute arbitrary code or cause a denial-of-service (DoS) condition via multipart/form-data format data.

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

## Which versions are affected by CVE-2018-0684?

It affects 2 products.


Products: Neo Debun Imap, Neo Debun Pop.

## How do I fix CVE-2018-0684?

No fix has been published for CVE-2018-0684 yet. Limit exposure of the affected software until one is available.

## Is CVE-2018-0684 being exploited?

There is no known exploitation of CVE-2018-0684 in the wild and no public exploit code.

## Other vulnerabilities in Denbun by NEOJAPAN Inc. (Denbun POP version V3.3P R3.0 and earlier, Denbun IMAP version V3.3I R3.0 and earlier)

- [CVE-2018-0680](https://insights.sbomify.com/CVE-2018-0680/): Hardcoded credentials in Denbun by NEOJAPAN Inc. (Denbun POP version V3.3P R4.0 and earlier, Denbun IMAP version V3.3I R4.0 and earlier) (critical 9.8)
- [CVE-2018-0681](https://insights.sbomify.com/CVE-2018-0681/): Hardcoded credentials in Denbun by NEOJAPAN Inc. (Denbun POP version V3.3P R4.0 and earlier, Denbun IMAP version V3.3I R4.0 and earlier) (critical 9.8)
- [CVE-2018-0682](https://insights.sbomify.com/CVE-2018-0682/): Missing authorization in Denbun by NEOJAPAN Inc. (Denbun POP version V3.3P R4.0 and earlier, Denbun IMAP version V3.3I R4.0 and earlier) (critical 9.8)
- [CVE-2018-0683](https://insights.sbomify.com/CVE-2018-0683/): Memory corruption in Denbun by NEOJAPAN Inc. (Denbun POP version V3.3P R4.0 and earlier, Denbun IMAP version V3.3I R4.0 and earlier) (critical 9.8)
- [CVE-2018-0686](https://insights.sbomify.com/CVE-2018-0686/): File upload in Denbun by NEOJAPAN Inc. (Denbun POP version V3.3P R4.0 and earlier, Denbun IMAP version V3.3I R4.0 and earlier) (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-0684 and fix it if it is affected.

What it is: CVE-2018-0684 is a critical memory corruption vulnerability in Denbun by NEOJAPAN Inc. (Denbun POP version V3.3P R3.0 and earlier, Denbun IMAP version V3.3I R3.0 and earlier), published on 15 Nov 2018. 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-2018-0684 in the wild and no public exploit code.

Affected product: Denbun by NEOJAPAN Inc. (Denbun POP version V3.3P R3.0 and earlier, Denbun IMAP version V3.3I R3.0 and earlier). 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-2018-0684/ (Markdown: https://insights.sbomify.com/CVE-2018-0684/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-0684
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-0684
- OSV: https://osv.dev/vulnerability/CVE-2018-0684

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From sbomify Insights: https://insights.sbomify.com/CVE-2018-0684/
Summaries are generated and may contain mistakes; the official description above is the record.