CVE-2026-49247
highpriority · track · 0EPSS 0.005 · 46 %ileEUEPSS · scored 2026-10-27
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.
cvss
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base score 0–10 · higher = more severe · hover a vector to decode
ssvc
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weaknesses
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affected products (1)
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also known as (2)
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sources
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references (3)
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