# CVE-2017-18594: Memory corruption in n/a

> A double free vulnerability in Nmap's SSH brute-force scripts allows remote attackers to cause a denial of service via crafted input.

- **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:** Yes
- **Published:** 28 Aug 2019
- **Updated:** 5 Aug 2024
- **Also known as:** ALPINE-CVE-2017-18594, DEBIAN-CVE-2017-18594, GHSA-mh4c-hqr8-mc3f, MGASA-2020-0216, UBUNTU-CVE-2017-18594, openSUSE-SU-2024:11750-1

## What is CVE-2017-18594?

CVE-2017-18594 is a high-severity memory corruption vulnerability in n/a, published on 28 Aug 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

nse_libssh2.cc in Nmap 7.70 is subject to a denial of service condition due to a double free when an SSH connection fails, as demonstrated by a leading \n character to ssh-brute.nse or ssh-auth-methods.nse.

Weakness: CWE-415 (Double Free)

## Which versions are affected by CVE-2017-18594?

It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `nmap` | openSUSE:Tumbleweed | All versions | 7.92-4.1 |

Products: Nmap Nmap.

## How do I fix CVE-2017-18594?

Upgrade to a fixed version.

## Is CVE-2017-18594 being exploited?

There is no known exploitation of CVE-2017-18594 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2018-15173](https://insights.sbomify.com/CVE-2018-15173/): Denial of service in n/a (high 7.5)
- [CVE-2026-58058](https://insights.sbomify.com/CVE-2026-58058/): Nmap - Integer Underflow in IPv6 Extension Header Parsing (medium 6.9)
- [CVE-2013-4885](https://insights.sbomify.com/CVE-2013-4885/): Path traversal in n/a (medium 6.8)
- [CVE-2018-1000161](https://insights.sbomify.com/CVE-2018-1000161/): Path traversal in n/a (medium 5.7)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2017-18594 and fix it if it is affected.

What it is: CVE-2017-18594 is a high-severity memory corruption vulnerability in n/a, published on 28 Aug 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-2017-18594 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-2017-18594/ (Markdown: https://insights.sbomify.com/CVE-2017-18594/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2017-18594
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2017-18594
- OSV: https://osv.dev/vulnerability/CVE-2017-18594

---
From sbomify Insights: https://insights.sbomify.com/CVE-2017-18594/
Summaries are generated and may contain mistakes; the official description above is the record.