# CVE-2019-9854: Unsafe URL assembly flaw in allowed script location check

> Attackers can bypass script location restrictions to execute arbitrary pre-installed macros via unsafe URL assembly in LibreOffice.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 6 Sep 2019
- **Updated:** 16 Sep 2024
- **Also known as:** DEBIAN-CVE-2019-9854, DSA-4519-1, GHSA-54x7-phmv-8vq8, UBUNTU-CVE-2019-9854, USN-4138-1

## What is CVE-2019-9854?

CVE-2019-9854 is a high-severity path traversal vulnerability in Canonical Ubuntu Linux, published on 6 Sep 2019. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

LibreOffice has a feature where documents can specify that pre-installed macros can be executed on various script events such as mouse-over, document-open etc. Access is intended to be restricted to scripts under the share/Scripts/python, user/Scripts/python sub-directories of the LibreOffice install. Protection was added, to address CVE-2019-9852, to avoid a directory traversal attack where scripts in arbitrary locations on the file system could be executed by employing a URL encoding attack to defeat the path verification step. However this protection could be bypassed by taking advantage of a flaw in how LibreOffice assembled the final script URL location directly from components of the passed in path as opposed to solely from the sanitized output of the path verification step. This issue affects: Document Foundation LibreOffice 6.2 versions prior to 6.2.7; 6.3 versions prior to 6.3.1.

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

## Which versions are affected by CVE-2019-9854?

It affects 6 products.


Products: Canonical Ubuntu Linux, Debian Debian Linux, Fedoraproject Fedora, Libreoffice Libreoffice, Opensuse Leap, Redhat Enterprise Linux.

## How do I fix CVE-2019-9854?

Upgrade to a fixed version.

## Is CVE-2019-9854 being exploited?

There is no known exploitation of CVE-2019-9854 in the wild and no public exploit code.

## Other vulnerabilities in Canonical Ubuntu Linux

- [CVE-2020-11651](https://insights.sbomify.com/CVE-2020-11651/): SaltStack Salt Authentication Bypass (critical 9.8, exploited in the wild)
- [CVE-2020-7247](https://insights.sbomify.com/CVE-2020-7247/): OpenSMTPD Remote Code Execution (critical 9.8, exploited in the wild)
- [CVE-2019-16928](https://insights.sbomify.com/CVE-2019-16928/): Exim Out-of-bounds Write (critical 9.8, exploited in the wild)
- [CVE-2018-6789](https://insights.sbomify.com/CVE-2018-6789/): Exim Buffer Overflow (critical 9.8, exploited in the wild)
- [CVE-2015-2590](https://insights.sbomify.com/CVE-2015-2590/): Oracle Java SE and Java SE Embedded Remote Code Execution (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-9854 and fix it if it is affected.

What it is: CVE-2019-9854 is a high-severity path traversal vulnerability in Canonical Ubuntu Linux, published on 6 Sep 2019. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2019-9854 in the wild and no public exploit code.

Affected product: Canonical Ubuntu Linux. 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-2019-9854/ (Markdown: https://insights.sbomify.com/CVE-2019-9854/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-9854
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-9854
- OSV: https://osv.dev/vulnerability/CVE-2019-9854

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-9854/
Summaries are generated and may contain mistakes; the official description above is the record.