Access Restriction Bypass Affecting mediabrowser.server.core package, versions [0,]

  • Exploit Maturity

    Proof of concept

  • Attack Complexity


  • Confidentiality


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  • snyk-id


  • published

    9 Sep 2021

  • disclosed

    9 Sep 2021

  • credit

    @JarLob (Jaroslav Lobačevski)

How to fix?

There is no fixed version for MediaBrowser.Server.Core.


MediaBrowser.Server.Core is a package that contains core components required to build plugins for Emby Server.

Affected versions of this package are vulnerable to Access Restriction Bypass. In Emby Server on Windows there are two arbitrary file read vulnerabilities.

The first is via /Videos/Id/hls/PlaylistId/SegmentId.SegmentContainer. It is possible to set the {SegmentId}.{SegmentContainer} part of the route to an absolute path using the Windows path separator \ (%5C when URL encoded). The PlaylistId doesn’t matter, but a prerequisite is a knowledge of the Id - a GUID of an existing media file. The Id can be leaked by any authenticated user as it is exposed in server responses.

Additionally, both the /Images/Ratings/{theme}/{name} and /Images/MediaInfo/{theme}/{name} routes allow unauthenticated arbitrary image file read on Windows. It is possible to set the {theme} or {name} part of the route to a relative or absolute path using the Windows path separator ``` (%5C when URL encoded). The route automatically appends the following allowed extensions, so it is only possible to read image files: .png, .jpg, .jpeg, .tbn, .gif.