# CVE-2019-18899: apt-cacher-ng insecure use of /run/apt-cacher-ng

> Local attackers can escalate privileges by exploiting root operations in a user-owned directory within the apt-cacher-ng package on openSUSE Leap.

- **Severity:** Medium 6.2 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 23 Jan 2020
- **Updated:** 17 Sep 2024
- **Also known as:** GHSA-fv3j-23hh-g3xf

## What is CVE-2019-18899?

CVE-2019-18899 is a medium-severity vulnerability in Opensuse Backports, published on 23 Jan 2020. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

The apt-cacher-ng package of openSUSE Leap 15.1 runs operations in user owned directory /run/apt-cacher-ng with root privileges. This can allow local attackers to influence the outcome of these operations. This issue affects: openSUSE Leap 15.1 apt-cacher-ng versions prior to 3.1-lp151.3.3.1.

Weakness: CWE-269 (Improper Privilege Management)

## Which versions are affected by CVE-2019-18899?

It affects 2 products.


Products: Apt-Cacher-Ng Project Apt-Cacher-Ng, Opensuse Backports.

## How do I fix CVE-2019-18899?

Apply the vendor's patch.

## Is CVE-2019-18899 being exploited?

There is no known exploitation of CVE-2019-18899 in the wild and no public exploit code.

## Other vulnerabilities in Opensuse Backports

- [CVE-2017-7443](https://insights.sbomify.com/CVE-2017-7443/): Other in n/a (medium 6.1)
- [CVE-2020-5202](https://insights.sbomify.com/CVE-2020-5202/): Information disclosure in n/a (medium 5.5)
- [CVE-2025-11146](https://insights.sbomify.com/CVE-2025-11146/): Reflected Cross-site scripting (XSS) vulnerability in Apt-Cacher-NG (medium 5.1)
- [CVE-2025-11147](https://insights.sbomify.com/CVE-2025-11147/): Reflected Cross-site scripting (XSS) vulnerability in Apt-Cacher-NG (medium 5.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-18899 and fix it if it is affected.

What it is: CVE-2019-18899 is a medium-severity vulnerability in Opensuse Backports, published on 23 Jan 2020. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2019-18899 in the wild and no public exploit code.

Affected product: Opensuse Backports. 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-2019-18899/ (Markdown: https://insights.sbomify.com/CVE-2019-18899/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-18899
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-18899
- OSV: https://osv.dev/vulnerability/CVE-2019-18899

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-18899/
Summaries are generated and may contain mistakes; the official description above is the record.