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 con...

Description

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.

Metrics

CVSS 3.1

8.8/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

0.36%

27.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-88

References

https://github.com/jellyfin/jellyfin/security/advisories/GHSA-wwwm-px48-fpvq

Timeline

Published: Jun 24, 2026
Last Modified: Jun 26, 2026
Status: Deferred

Frequently Asked Questions

What is 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.

How severe is CVE-2026-48793?

CVE-2026-48793 has a CVSS score of 8.8/10 (HIGH severity). The EPSS model estimates a 0.36% probability of exploitation in the next 30 days.

How do I fix CVE-2026-48793?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.