# CVE-2021-34808: Server-side request forgery in Media Server

> Remote attackers can access intranet resources via SSRF in Synology Media Server, requiring an upgrade to mitigate.

- **Severity:** Medium 5.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/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:** No
- **Published:** 18 Jun 2021
- **Updated:** 17 Sep 2024
- **Also known as:** GHSA-x9fw-v6jg-w952

## What is CVE-2021-34808?

CVE-2021-34808 is a medium-severity server-side request forgery vulnerability in Synology Media Server, published on 18 Jun 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Server-Side Request Forgery (SSRF) vulnerability in cgi component in Synology Media Server before 1.8.3-2881 allows remote attackers to access intranet resources via unspecified vectors.

Weakness: CWE-918 (Server-Side Request Forgery)

## Which versions are affected by CVE-2021-34808?

It affects 1 product.


Products: Synology Media Server.

## How do I fix CVE-2021-34808?

No fix has been published for CVE-2021-34808 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-34808 being exploited?

There is no known exploitation of CVE-2021-34808 in the wild and no public exploit code.

## Other vulnerabilities in Synology Media Server

- [CVE-2022-22683](https://insights.sbomify.com/CVE-2022-22683/): Memory corruption in Media Server (critical 10.0)
- [CVE-2024-4464](https://insights.sbomify.com/CVE-2024-4464/): Missing authorization in Media Server (high 7.5)
- [CVE-2021-33180](https://insights.sbomify.com/CVE-2021-33180/): SQL injection in Synology Media Server (high 7.3)
- [CVE-2018-8914](https://insights.sbomify.com/CVE-2018-8914/): SQL injection in Media Server (high 7.3)
- [CVE-2022-27614](https://insights.sbomify.com/CVE-2022-27614/): Information disclosure in Media Server (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-34808 and fix it if it is affected.

What it is: CVE-2021-34808 is a medium-severity server-side request forgery vulnerability in Synology Media Server, published on 18 Jun 2021. 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-2021-34808 in the wild and no public exploit code.

Affected product: Synology Media Server. 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-2021-34808/ (Markdown: https://insights.sbomify.com/CVE-2021-34808/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-34808
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-34808
- OSV: https://osv.dev/vulnerability/CVE-2021-34808

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-34808/
Summaries are generated and may contain mistakes; the official description above is the record.