CVE-2026-49246: low-severity vulnerability in jellyfin
Jellyfin: Potential MKV attachment filename path traversal to RCE
Published · Updated
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8Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 1.7epss 0.4%
Jellyfin is an open source self hosted media server. Prior to 10.11.10, a specifically crafted MKV file containing forged filename tags can be leveraged to exploit missing path sanitization during playback. Jellyfin treats the MKV file name tag on MKV attachments as trusted and passes it unsanitized into Path.Combine(attachmentFolder, fileName) inside PathManager.GetAttachmentPath. Because .NET's Path.Combine neither normalises .. nor rejects a rooted second argument, a crafted MKV can redirect Jellyfin's MKV attachment extraction to any absolute path on disk. This triggers on any playback action of the affected video on a client which will attempt to burn in the subtitles by default.g This vulnerability is fixed in 10.11.10.
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U
Affected products
jellyfin · jellyfinRelated CVEs — jellyfin
In the same product, most dangerous first.
CVE-2021-21402HIGHUnauthenticated Arbitrary File Access in JellyfinEPSS 79.3%CVE-2021-29490MEDIUMUnauthenticated GET requests through Remote Image endpointsEPSS 71.7%CVE-2023-30626HIGHJellyfin vulnerable to directory traversal and file write causing arbitrary code executionEPSS 2.0%CVE-2023-49096HIGHArgument Injection in FFmpeg codec parameters in JellyfinEPSS 1.3%CVE-2023-48702HIGHJellyfin Possible Remote Code Execution via custom FFmpeg binaryEPSS 1.2%CVE-2025-31499HIGHJellyfin Vulnerable to Argument Injection in FFmpegEPSS 0.8%