What is the CVSS score of CVE-2026-48793?

CVE-2026-48793 has a CVSS 3.1 base score of 8.8 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.4%.

Which versions of Jellyfin are affected by CVE-2026-48793?

Jellyfin media servers running versions prior to 10.11.10 are vulnerable to an unauthenticated attack that allows threat actors to write arbitrary files and disclose sensitive information through…. A patch is available.

How to fix or mitigate CVE-2026-48793?

Within 24 hours: Inventory all Jellyfin deployments and identify instances accessible from the internet or untrusted networks. Within 7 days: Upgrade all Jellyfin instances to version 10.11.10 or later. Within 30 days: Implement network access controls restricting Jellyfin instances to trusted networks only; conduct forensic review of media library directories for suspicious files.

Jellyfin CVE-2026-48793

EUVD-2026-39030 HIGH

Improper Neutralization of Argument Delimiters in a Command ('Argument Injection') (CWE-88)

2026-06-24 GitHub_M

Information Disclosure Jellyfin

8.8

CVSS 3.1 · Vendor: GitHub_M

Severity by source

Vendor (GitHub_M) PRIMARY

8.8 HIGH

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

vuln.today AI

7.1 HIGH

Network-triggered but requires writable-share file placement and a Linux quote-permitting filename, so PR:L and AC:H; arbitrary file write yields C:H/I:H with limited availability impact.

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

4.0 AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N

Primary rating from Vendor (GitHub_M).

CVSS VectorVendor: GitHub_M

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

Patch available

Jun 24, 2026 - 20:03 EUVD

Analysis Generated

Jun 24, 2026 - 19:18 vuln.today

CVE Published

Jun 24, 2026 - 18:22 cve.org

HIGH 8.8

DescriptionCVE.org

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.

AnalysisAI

Arbitrary file write and information disclosure in Jellyfin self-hosted media server (all versions prior to 10.11.10) arise from FFmpeg argument injection in the subtitle conversion path. Because SubtitleController.GetSubtitle carries no [Authorize] attribute, an attacker who can place a maliciously named file into a Jellyfin media library directory (e.g., via a shared NAS, Samba share, or guest upload) can break FFmpeg's argument quoting on Linux and inject arbitrary FFmpeg flags. There is no public exploit identified at time of analysis and the CVE is not listed in CISA KEV, but the unauthenticated endpoint and high CVSS (8.8) make it a meaningful concern for exposed instances.

Technical ContextAI

Jellyfin transcodes and remuxes media using FFmpeg invoked as an external process with interpolated command-line arguments. The flaw (CWE-88, Argument Injection) lives in SubtitleEncoder.ConvertTextSubtitleToSrtInternal at SubtitleEncoder.cs line 382, which builds the FFmpeg command by interpolating the subtitle file path directly into the argument string without first passing it through EncodingUtils.NormalizePath(). On Linux, filenames may legally contain double-quote characters; an embedded quote terminates the intended quoted argument early, letting the remainder of the filename be parsed by FFmpeg as additional CLI options. FFmpeg's rich option set (including output/muxer and file-handling options) is what converts that injection into arbitrary file write and data disclosure. The affected component is identified by cpe:2.3:a:jellyfin:jellyfin:*:*:*:*:*:*:*:* covering all releases before the fixed 10.11.10.

RemediationAI

Vendor-released patch: 10.11.10 - upgrade all Jellyfin instances to 10.11.10 or later, per the advisory at https://github.com/jellyfin/jellyfin/security/advisories/GHSA-wwwm-px48-fpvq. If immediate patching is not possible, reduce who can place files into media library directories: revoke guest/anonymous upload permissions, make Samba/NFS/NAS shares feeding Jellyfin read-only or write-restricted to trusted accounts, and disallow filenames containing double-quote characters on those shares (trade-off: may reject some legitimate but unusually named files). Restrict network exposure of the Jellyfin instance and specifically the unauthenticated subtitle endpoint (SubtitleController.GetSubtitle) to trusted networks via reverse-proxy access control or firewall rules (trade-off: remote/mobile access may break). These are compensating controls only; they narrow but do not eliminate the file-placement attack surface, so prioritize the upgrade.