Vulnerability in Jellyfin

CVE-2026-48793

Jellyfin is an open source self hosted media server. Prior to 10.11.10, a potential FFmpeg argument injection vulnerability exists in the subtitle conversion code path. SubtitleEncoder.ConvertTextSubtitleToSrtInternal (SubtitleEncoder.cs, line 382) interpolates the subtitle file path into FFmpeg command-line arguments without calling EncodingUtils.NormalizePath(). On Linux, filenames can contain double-quote characters, which break the argument quoting and allow injection of arbitrary FFmpeg arguments. The vulnerability is reachable without authentication via SubtitleController.GetSubtitle, which has no [Authorize] attribute. An attacker who can place a file in a Jellyfin media library directory (shared NAS, Samba share, guest upload) can achieve arbitrary file write on the server and information disclosure. This vulnerability is fixed in 10.11.10.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.007 (49.8th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 50th percentile — 49.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-48793: held from 0.007 to 0.007.

EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-48793?
CVE-2026-48793 is a high-severity vulnerability in Jellyfin, classified under Argument Injection. CVSS score: 8.8/10. Published 2026-06-24.
How severe is CVE-2026-48793?
High severity. CVSS v3 base score is 8.8 out of 10.