CVE-2026-35034
Jellyfin: Potential Application DoS from excessively large SyncPlay group names
Description
Jellyfin is an open source self hosted media server. Versions prior to 10.11.7 contain a denial of service vulnerability in the SyncPlay group creation endpoint (POST /SyncPlay/New), where an authenticated user can create groups with names of unlimited size due to insufficient input validation. By sending large payloads combined with arbitrary group IDs, an attacker can lock out the endpoint for other clients attempting to join SyncPlay groups and significantly increase the memory usage of the Jellyfin process, potentially leading to an out-of-memory crash. This issue has been fixed in version 10.11.7.
INFO
Published Date :
April 14, 2026, 11:16 p.m.
Last Modified :
July 24, 2026, 9:10 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update Jellyfin to version 10.11.7.
- Apply vendor patches if available.
- Restart the Jellyfin service.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-35034.
| URL | Resource |
|---|---|
| https://github.com/jellyfin/jellyfin/releases/tag/v10.11.7 | Product Release Notes |
| https://github.com/jellyfin/jellyfin/security/advisories/GHSA-v2jv-54xj-h76w | Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-35034 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-35034
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-35034 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-35034 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Translated by [email protected]
Jul. 24, 2026
Action Type Old Value New Value Added Translation Title: Jellyfin, Description: Jellyfin es un servidor de medios de código abierto autoalojado. Versiones anteriores a la 10.11.7 contienen una vulnerabilidad de denegación de servicio en el endpoint de creación de grupos de SyncPlay (POST /SyncPlay/New), donde un usuario autenticado puede crear grupos con nombres de tamaño ilimitado debido a una validación de entrada insuficiente. Al enviar grandes cargas útiles combinadas con IDs de grupo arbitrarios, un atacante puede bloquear el endpoint para otros clientes que intentan unirse a grupos de SyncPlay y aumentar significativamente el uso de memoria del proceso de Jellyfin, lo que podría llevar a un fallo por falta de memoria. Este problema ha sido solucionado en la versión 10.11.7. -
CVE Modified by [email protected]
Jun. 17, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'jellyfin', 'product': 'jellyfin', 'versions': [{'status': 'affected', 'version': '< 10.11.7'}]}] -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 17, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-35034', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-04-15T17:48:33.580055Z'} -
Initial Analysis by [email protected]
Apr. 23, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:jellyfin:jellyfin:*:*:*:*:*:*:*:* versions up to (excluding) 10.11.7 Added Reference Type GitHub, Inc.: https://github.com/jellyfin/jellyfin/releases/tag/v10.11.7 Types: Product, Release Notes Added Reference Type GitHub, Inc.: https://github.com/jellyfin/jellyfin/security/advisories/GHSA-v2jv-54xj-h76w Types: Vendor Advisory -
New CVE Received by [email protected]
Apr. 14, 2026
Action Type Old Value New Value Added Description Jellyfin is an open source self hosted media server. Versions prior to 10.11.7 contain a denial of service vulnerability in the SyncPlay group creation endpoint (POST /SyncPlay/New), where an authenticated user can create groups with names of unlimited size due to insufficient input validation. By sending large payloads combined with arbitrary group IDs, an attacker can lock out the endpoint for other clients attempting to join SyncPlay groups and significantly increase the memory usage of the Jellyfin process, potentially leading to an out-of-memory crash. This issue has been fixed in version 10.11.7. Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Added CWE CWE-400 Added Reference https://github.com/jellyfin/jellyfin/releases/tag/v10.11.7 Added Reference https://github.com/jellyfin/jellyfin/security/advisories/GHSA-v2jv-54xj-h76w