# CVE-2026-35033: Jellyfin ffmpeg argument injection arbitrary file read in StreamOptions

Source: https://junglewise.ai/threats/cve-2026-35033-jellyfin-ffmpeg-argument-injection-arbitrary-file-read-in  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-04-14. Updated: 2026-07-24  
License: CC BY 4.0 with a link back

CVE-2026-35033 · Severity: critical · CVSS 9.1 · Published 2026-04-14

Jellyfin is an open-source media server used to host and stream personal video and audio collections. A security flaw allows unauthorized users to trick the server into reading sensitive system files (such as passwords or configuration data) and displaying their contents inside a video stream. This could lead to a full system compromise or the theft of sensitive administrative data.

Technologies: [Jellyfin](https://junglewise.ai/threats/technologies/jellyfin). Vendors: [Jellyfin](https://junglewise.ai/threats/vendors/jellyfin).

## Quick answers

**Is CVE-2026-35033 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-35033 being exploited in the wild.

**How severe is CVE-2026-35033?** Critical severity, with a CVSS score of 9.1, published 14 April 2026.

**Which products and versions are affected?** Jellyfin < 10.11.7.

**Is there a fix for CVE-2026-35033?** A patch was published on 2023-03-31: Version 10.11.7 released Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-35033 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-35033?** Check whether you run Jellyfin at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

An argument injection vulnerability exists in Jellyfin's `ParseStreamOptions` method within `StreamingHelpers.cs`. The application fails to validate lowercase query parameters, allowing an attacker to bypass regex filters and inject arbitrary arguments into the ffmpeg command line. Specifically, by manipulating the `h264-level` parameter, an attacker can inject a `drawtext` filter with a `textfile` argument to read files like `/etc/shadow`. While the `/Videos/{itemId}/stream` endpoint lacks an authorization attribute, an attacker must still know or obtain a pseudorandom item GUID to successfully trigger the exploit. The issue is resolved in version 10.11.7 by improving input sanitization.

## Affected products

- Jellyfin Jellyfin < 10.11.7

## Timeline

- 2023-03-31: patched: Version 10.11.7 released
- 2026-04-14: advisory: Security advisory and CVE published

## References

- [https://github.com/jellyfin/jellyfin/releases/tag/v10.11.7](https://github.com/jellyfin/jellyfin/releases/tag/v10.11.7)
- [https://github.com/jellyfin/jellyfin/security/advisories/GHSA-jh22-fw8w-2v9x](https://github.com/jellyfin/jellyfin/security/advisories/GHSA-jh22-fw8w-2v9x)

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