# CVE-2018-20658: Denial of service in n/a

> Remote attackers can crash the Core FTP server daemon on 32-bit platforms by sending a crafted XRMD command.

- **Severity:** High 7.5 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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:** 2 Jan 2019
- **Updated:** 16 Sep 2024
- **Also known as:** GHSA-7wjj-g2fp-6r9j

## What is CVE-2018-20658?

CVE-2018-20658 is a high-severity denial of service vulnerability in n/a, published on 2 Jan 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The server in Core FTP 2.0 build 653 on 32-bit platforms allows remote attackers to cause a denial of service (daemon crash) via a crafted XRMD command.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2018-20658?

It affects 1 product.


Products: Coreftp Core Ftp.

## How do I fix CVE-2018-20658?

No fix has been published for CVE-2018-20658 yet. Limit exposure of the affected software until one is available.

## Is CVE-2018-20658 being exploited?

There is no known exploitation of CVE-2018-20658 in the wild and no public exploit code.

Public exploit code:

- Core FTP 2.0 - 'XRMD' Denial of Service (PoC) (exploitdb)

## Other vulnerabilities in n/a

- [CVE-2020-19596](https://insights.sbomify.com/CVE-2020-19596/): Memory corruption in n/a (critical 9.8)
- [CVE-2018-12113](https://insights.sbomify.com/CVE-2018-12113/): Memory corruption in n/a (critical 9.8)
- [CVE-2013-3930](https://insights.sbomify.com/CVE-2013-3930/): Memory corruption in n/a (critical 9.3)
- [CVE-2009-3484](https://insights.sbomify.com/CVE-2009-3484/): Memory corruption in n/a (critical 9.3)
- [CVE-2019-25686](https://insights.sbomify.com/CVE-2019-25686/): Core FTP 2.0 build 653 PBSZ Unauthenticated Denial of Service (high 8.7)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-20658 and fix it if it is affected.

What it is: CVE-2018-20658 is a high-severity denial of service vulnerability in n/a, published on 2 Jan 2019. 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-2018-20658 in the wild and no public exploit code.

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-2018-20658/ (Markdown: https://insights.sbomify.com/CVE-2018-20658/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-20658
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-20658
- OSV: https://osv.dev/vulnerability/CVE-2018-20658

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-20658/
Summaries are generated and may contain mistakes; the official description above is the record.