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TI-2026-36444 Aliases CVE-2026-49247

Jellyfin: Potential Authenticated path traversal in /ClientLog/Document

Priority MEDIUM 41CWE-22Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00548 46th percentileScored 2026-11-07
Fix Fixed jellyfin (jellyfin): 10.11.10

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

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

Affected products

VendorProductAffected versionsFixed inStatusSource
jellyfinjellyfin10.9.0 to before 10.11.1010.11.10Patch availableCNA
  • jellyfin Vendorjellyfin Affected 10.9.0 to before 10.11.10 Fixed in 10.11.10 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:jellyfin:jellyfin:*:*:*:*:*:*:*:*——jellyfin
  • cpe:2.3:a:jellyfin:jellyfin:*:*:*:*:*:*:*:* Versions — — ·jellyfin

Remediation

  • Fix · CNA jellyfin (jellyfin) Fixed in 10.11.10

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-49247

References

  • 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 25 →

Sources

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