Jellyfin: Potential Authenticated path traversal in /ClientLog/Document_CVE-2026-49247

8.8 / 10

HIGH

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

Description

Jellyfin is an open source self hosted media server. From 10.9.0 until 10.11.10, the POST /ClientLog/Document endpoint accepts the Authorization header's Client and Version fields and uses them unsanitized as components of the on-disk filename when persisting client-uploaded log documents. As a result, any authenticated non-admin user can include ../ sequences in the Client field to cause Jellyfin to write attacker-controlled content to arbitrary paths reachable by the Jellyfin service user, with a forced .log suffix. This vulnerability is fixed in 10.11.10.

AI Analysis

Authenticated path traversal vulnerability in Jellyfin's /ClientLog/Document endpoint, allowing attackers to write arbitrary files with a .log suffix.

Basic Information

ID CVE-2026-49247

Source GitHub_M

Published Jun 24, 2026 at 18:18

Affected Product

Vendor jellyfin

Product jellyfin

Version >= 10.9.0, < 10.11.10

Affected Versions jellyfin jellyfin >= 10.9.0, < 10.11.10

CWE Classification

CWE-22

AI Assessment

AI Score 8.8 / 10

AI Severity High

Vendor Jellyfin

Product Jellyfin Media Server

Version 10.9.0 to 10.11.10

References

github.com /jellyfin/jellyfin/security/advisories/GHSA-jg92-mrxq-vv75

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