# CVE-2018-8921: Cross-site scripting in Drive

> Remote authenticated users can inject arbitrary web script or HTML via malicious file names in Synology Drive.

- **Severity:** Medium 6.5 (`CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 1 Jun 2018
- **Updated:** 16 Sep 2024
- **Also known as:** GHSA-56rc-gpxm-rv3v

## What is CVE-2018-8921?

CVE-2018-8921 is a medium-severity cross-site scripting vulnerability in Synology Drive, published on 1 Jun 2018. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

Cross-site scripting (XSS) vulnerability in File Sharing Notify Toast in Synology Drive before 1.0.2-10275 allows remote authenticated users to inject arbitrary web script or HTML via the malicious file name.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation)

## Which versions are affected by CVE-2018-8921?

It affects 1 product.


Products: Synology Drive Server.

## How do I fix CVE-2018-8921?

No fix has been published for CVE-2018-8921 yet. Limit exposure of the affected software until one is available.

## Is CVE-2018-8921 being exploited?

There is no known exploitation of CVE-2018-8921 in the wild and no public exploit code.

## Other vulnerabilities in Synology Drive

- [CVE-2024-50630](https://insights.sbomify.com/CVE-2024-50630/): Missing authorization in Synology Drive Server (high 7.5)
- [CVE-2024-50631](https://insights.sbomify.com/CVE-2024-50631/): SQL injection in Synology Drive Server (high 7.5)
- [CVE-2018-8922](https://insights.sbomify.com/CVE-2018-8922/): Missing authorization in Drive (medium 6.5)
- [CVE-2018-8910](https://insights.sbomify.com/CVE-2018-8910/): Cross-site scripting in Drive (medium 6.5)
- [CVE-2018-13297](https://insights.sbomify.com/CVE-2018-13297/): Information disclosure in Drive (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-8921 and fix it if it is affected.

What it is: CVE-2018-8921 is a medium-severity cross-site scripting vulnerability in Synology Drive, published on 1 Jun 2018. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2018-8921 in the wild and no public exploit code.

Affected product: Synology Drive. 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-2018-8921/ (Markdown: https://insights.sbomify.com/CVE-2018-8921/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-8921
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-8921
- OSV: https://osv.dev/vulnerability/CVE-2018-8921

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-8921/
Summaries are generated and may contain mistakes; the official description above is the record.