CVE-2026-35031
highpriority · attend · 45EPSS 0.008 · 55 %ileexploit · PoCEUUSEPSS · scored 2026-10-27
Jellyfin is an open source self hosted media server. Versions prior to 10.11.7 contain a vulnerability chain in the subtitle upload endpoint (POST /Videos/{itemId}/Subtitles), where the Format field is not validated, allowing path traversal via the file extension and enabling arbitrary file write. This arbitrary file write can be chained into arbitrary file read via .strm files, database extraction, admin privilege escalation, and ultimately remote code execution as root via ld.so.preload. Exploitation requires an administrator account or a user that has been explicitly granted the "Upload Subtitles" permission. This issue has been fixed in version 10.11.7. If users are unable to upgrade immediately, they can grant non-administrator users Subtitle upload permissions to reduce attack surface.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 8.3–10
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
exploits (1)
Public proof-of-concept and weaponised exploit code.
affected products (2)
Products and version ranges known to be affected.
also known as (2)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (8)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/cve-2026-35031cnnvd
- https://github.com/jellyfin/jellyfin/releases/Patchcnnvd
- https://github.com/jellyfin/jellyfin/releases/tag/v10.11.7cnnvd
- https://github.com/jellyfin/jellyfin/security/advisories/GHSA-j2hf-x4q5-47j3cnnvd
- https://github.com/jellyfin/jellyfin/releases/tag/v10.11.7enisa_euvd
- https://github.com/jellyfin/jellyfin/security/advisories/GHSA-j2hf-x4q5-47j3enisa_euvd
- https://github.com/jellyfin/jellyfin/releases/tag/v10.11.7ProductRelease Notesnvd
- https://github.com/jellyfin/jellyfin/security/advisories/GHSA-j2hf-x4q5-47j3MitigationVendor Advisorynvd
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