Vulnerability · Published Apr 14, 2026 · Assigned by GitHub_M
CVE-2026-35033Jellyfin: Potential SSRF + Arbitrary file read via stream argument injection
Critical 9.3
In plain English
A critical-severity argument injection in jellyfin from jellyfin. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 25% of all known vulnerabilities).
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.
Affected products (as reported)
Weakness: CWE-88, CWE-862 · Vector: 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
References
- https://github.com/jellyfin/jellyfin/security/advisories/GHSA-jh22-fw8w-2v9x x_refsource_CONFIRM
- https://github.com/jellyfin/jellyfin/releases/tag/v10.11.7 x_refsource_MISC