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TI-2026-27237 Aliases CVE-2026-35034

Jellyfin: Potential Application DoS from excessively large SyncPlay group names

Priority LOW 28CWE-400Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-400.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0026 17th percentileScored 2026-11-07
Fix Fixed jellyfin (jellyfin): 10.11.7

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
jellyfinjellyfinbefore 10.11.710.11.7Patch availableCNA
  • jellyfin Vendorjellyfin Affected before 10.11.7 Fixed in 10.11.7 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:jellyfin:jellyfin:*:*:*:*:*:*:*:*before 10.11.7Vulnerablejellyfin
  • cpe:2.3:a:jellyfin:jellyfin:*:*:*:*:*:*:*:* Versions before 10.11.7 Vulnerable ·jellyfin

Remediation

  • Fix · CNA jellyfin (jellyfin) Fixed in 10.11.7

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-35034

References

Advisory 1

Other 1

  • TI-2021-04500 Unauthenticated Arbitrary File Access in Jellyfin CVSS 3.1HIGH 7.7
  • TI-2023-26761 Argument Injection in FFmpeg codec parameters in Jellyfin CVSS 3.1HIGH 8.8
  • TI-2021-10203 Unauthenticated GET requests through Remote Image endpoints CVSS 3.1MEDIUM 5.8
  • TI-2023-09464 In Jellyfin 10.8.x through 10.8.3, the name of a playlist is vulnerable to stored XSS. CVSS 3.1MEDIUM 5.4
  • TI-2023-09463 In Jellyfin 10.8.x through 10.8.3, the name of a collection is vulnerable to stored XSS. CVSS 3.1MEDIUM 5.4
  • TI-2026-24405 Jellyfin Possible Organization/Secret Compromise from dangerous CI implementation CVSS 3.1CRITICAL 10.0
See all 18 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences