# CVE-2018-18586: Path traversal in n/a

> The chmextract sample program in libmspack allows directory traversal via malicious CHM files, enabling unauthorized file access or modification.

- **Severity:** Medium 5.3 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 23 Oct 2018
- **Updated:** 5 Aug 2024
- **Also known as:** ALPINE-CVE-2018-18586, DEBIAN-CVE-2018-18586, GHSA-jcvf-2rhc-m6h8, SUSE-SU-2022:0069-1, SUSE-SU-2022:0069-2, SUSE-SU-2022:4287-1, openSUSE-SU-2022:0069-1

## What is CVE-2018-18586?

CVE-2018-18586 is a medium-severity path traversal vulnerability in n/a, published on 23 Oct 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

chmextract.c in the chmextract sample program, as distributed with libmspack before 0.8alpha, does not protect against absolute/relative pathnames in CHM files, leading to Directory Traversal. NOTE: the vendor disputes that this is a libmspack vulnerability, because chmextract.c was only intended as a source-code example, not a supported application

Weakness: CWE-22 (Improper Limitation of a Pathname to a Restricted Directory)

## Which versions are affected by CVE-2018-18586?

It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `libmspack` | SUSE:Linux Enterprise Micro 5.0 | All versions | 0.6-3.14.1 |
| `libmspack` | SUSE:Linux Enterprise Micro 5.1 | All versions | 0.6-3.14.1 |
| `libmspack` | SUSE:Linux Enterprise Module for Basesystem 15 SP3 | All versions | 0.6-3.14.1 |
| `libmspack` | SUSE:Linux Enterprise Real Time 15 SP2 | All versions | 0.6-3.14.1 |
| `libmspack` | SUSE:Linux Enterprise Server 12 SP5 | All versions | 0.4-15.13.1 |
| `libmspack` | SUSE:Linux Enterprise Server for SAP Applications 12 SP5 | All versions | 0.4-15.13.1 |
| `libmspack` | SUSE:Linux Enterprise Software Development Kit 12 SP5 | All versions | 0.4-15.13.1 |
| `libmspack` | openSUSE:Leap 15.3 | All versions | 0.6-3.14.1 |

Products: Kyzer Libmspack.

## How do I fix CVE-2018-18586?

Upgrade to a fixed version.

## Is CVE-2018-18586 being exploited?

There is no known exploitation of CVE-2018-18586 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-18586 and fix it if it is affected.

What it is: CVE-2018-18586 is a medium-severity path traversal vulnerability in n/a, published on 23 Oct 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-2018-18586 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-2018-18586/ (Markdown: https://insights.sbomify.com/CVE-2018-18586/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-18586
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-18586
- OSV: https://osv.dev/vulnerability/CVE-2018-18586

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-18586/
Summaries are generated and may contain mistakes; the official description above is the record.