CVE-2026-35032

Jellyfin prior to version 10.11.7 has an unauthenticated arbitrary file read vulnerability via ffmpeg argument injection through the StreamOptions parameter. An attacker can read server files such as /etc/shadow and exfiltrate their contents as text in the video stream response.

Jellyfin versions prior to 10.11.7 contain a vulnerability chain in the subtitle upload endpoint (POST /Videos/{itemId}/Subtitles), where the Format field is not validated, allowing path traversal via file extension and arbitrary file write. This can be chained into arbitrary file read via .strm files, database extraction, admin privilege escalation, and ultimately remote code execution as root via ld.so.preload.

Jellyfin prior to version 10.11.10 has a vulnerability that allows a specially crafted MKV file with forged filename tags to exploit missing path sanitization during playback. As a result, a malicious MKV file can redirect attachment extraction to any absolute path on disk.

Jellyfin, an open-source media server, prior to version 10.11.9, had a potential XSS vulnerability that allowed a non-privileged user to execute arbitrary Javascript in the context of a logged-in Administrative user. The attack could occur through the Client header during AuthenticateByName.

Jellyfin before version 10.11.7 contains a denial of service vulnerability in the SyncPlay group creation endpoint. An authenticated user can create groups with unlimited name sizes, leading to endpoint lockout and increased memory usage, potentially causing an out-of-memory crash.

An SSRF vulnerability in Jellyfin up to version 10.7.7 allows an attacker to send a crafted POST request to the /Repositories component, enabling access to network resources and sensitive information.