CVE intelligence and bounded remediation

CVE-2021-32833 — Emby Server is a personal media server with apps on many devices

High CVSS 8.6

Emby Server is a personal media server with apps on many devices. In Emby Server on Windows there is a set of arbitrary file read vulnerabilities. This vulnerability is known to exist in version 4.6.4.0 and may not be patched in later versions. Known vulnerable routes are /Videos/Id/hls/PlaylistId/SegmentId.SegmentContainer, /Images/Ratings/theme/name and /Images/MediaInfo/theme/name. For more details including proof of concept code, refer to the referenced GHSL-2021-051. This issue may lead to unauthorized access to the system especially when Emby Server is configured to be accessible from the Internet.

Severity
High
CVSS
8.6 (3.1)
Published
2021-09-09
CISA KEV
Not currently listed
Ecosystem
windows/system
Weaknesses
CWE-552

Affected products

  • emby / emby.releases

Matched remediation archetype

Path traversal, unsafe upload, and file handling

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Trace untrusted filenames, archive entries, URLs, and path segments into read, write, include, extraction, and upload operations.
  • Identify filesystem roots, mount permissions, symbolic-link behavior, archive handling, and whether uploaded content is web-accessible or executable.
  • Review canonicalization and containment checks across supported operating systems and storage backends.

Remediate safely

  • Generate server-side storage identifiers and resolve paths beneath a fixed root using filesystem-aware containment checks.
  • Reject absolute, parent-relative, alternate-separator, device, link, and archive entries that escape the intended root.
  • Store uploads outside executable or served paths, validate type and size, and use private atomic temporary files.

Authoritative sources

Complete CVE record and remediation plan

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