External Control of File Name or Path Affecting jellyfin.controller package, versions [,10.11.7)
Threat Intelligence
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Test your applications- Snyk IDSNYK-DOTNET-JELLYFINCONTROLLER-16068202
- published15 Apr 2026
- disclosed14 Apr 2026
- creditodgrso, Piotr Niełacny, Bas
Introduced: 14 Apr 2026
NewCVE-2026-35031 (opens in a new tab)How to fix?
Upgrade Jellyfin.Controller to version 10.11.7 or higher.
Overview
Affected versions of this package are vulnerable to External Control of File Name or Path in the POST /Videos/{itemId}/Subtitles endpoint due to insufficient validation of the Format field, which allows path traversal via the file extension and enables arbitrary file write. An attacker can achieve arbitrary file read, database extraction, privilege escalation, and ultimately execute code as root by chaining this with .strm files and manipulating ld.so.preload. This is only exploitable if the attacker has an administrator account or has been explicitly granted the "Upload Subtitles" permission.