# CVE-2026-35033: Jellyfin: Potential SSRF + Arbitrary file read via stream argument injection

> Unauthenticated attackers can inject ffmpeg arguments to read arbitrary server files and potentially execute code via the stream endpoint.

- **Severity:** Critical 9.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:L/SI:L/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 14 Apr 2026
- **Updated:** 15 Apr 2026
- **Also known as:** GHSA-jh22-fw8w-2v9x

## What is CVE-2026-35033?

CVE-2026-35033 is a critical command injection vulnerability in jellyfin, published on 14 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Jellyfin is an open source self hosted media server. Versions prior to 10.11.7 contain an unauthenticated arbitrary file read vulnerability via ffmpeg argument injection through the StreamOptions query parameter parsing mechanism. The ParseStreamOptions method in StreamingHelpers.cs adds any lowercase query parameter to a dictionary without validation, bypassing the RegularExpression attribute on the level controller parameter, and the unsanitized value is concatenated directly into the ffmpeg command line. By injecting a drawtext filter with a textfile argument, an attacker can read arbitrary server files such as /etc/shadow and exfiltrate their contents as text rendered in the video stream response. The vulnerable /Videos/{itemId}/stream endpoint has no Authorize attribute, making this exploitable without authentication, though item GUIDs are pseudorandom and require an authenticated user to obtain. This issue has been fixed in version 10.11.7.

Weakness: CWE-88 (Improper Neutralization of Argument Delimiters in a Command), CWE-862 (Missing Authorization)

## Which versions are affected by CVE-2026-35033?

It affects 1 product.


Products: Jellyfin Jellyfin.

## How do I fix CVE-2026-35033?

No fix has been published for CVE-2026-35033 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-35033 being exploited?

There is no known exploitation of CVE-2026-35033 in the wild and no public exploit code.

## Other vulnerabilities in jellyfin

- [CVE-2026-35031](https://insights.sbomify.com/CVE-2026-35031/): Jellyfin: Potential RCE via subtitle upload path traversal + .strm chain (critical 10.0)
- [CVE-2026-31852](https://insights.sbomify.com/CVE-2026-31852/): Jellyfin Possible Organization/Secret Compromise from dangerous CI implementation (critical 10.0)
- [CVE-2023-30627](https://insights.sbomify.com/CVE-2023-30627/): jellyfin-web has a stored cross-site scripting vulnerability in devices.js (critical 9.1)
- [CVE-2023-30626](https://insights.sbomify.com/CVE-2023-30626/): Jellyfin vulnerable to directory traversal and file write causing arbitrary code execution (high 8.8)
- [CVE-2022-35909](https://insights.sbomify.com/CVE-2022-35909/): Incorrect Access Control and Cross Site Scripting in Jellyfin (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-35033 and fix it if it is affected.

What it is: CVE-2026-35033 is a critical command injection vulnerability in jellyfin, published on 14 Apr 2026. 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-2026-35033 in the wild and no public exploit code.

Affected product: jellyfin. 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-2026-35033/ (Markdown: https://insights.sbomify.com/CVE-2026-35033/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-35033
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-35033
- OSV: https://osv.dev/vulnerability/CVE-2026-35033

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-35033/
Summaries are generated and may contain mistakes; the official description above is the record.