Kavita is a cross platform reading server. Prior to 0.9.0, the download, size-check, and chapter metadata endpoints do not enforce library-level authorization. A low-privileged user who knows or guesses a chapterId, volumeId, or seriesId belonging to a library they are not assigned to can download the full file contents, query file sizes, and read metadata for that content. This affects /api/Download/volume-size, /api/Download/chapter-size, /api/Download/series-size, /api/Download/volume, /api/Download/chapter, /api/Download/series, and /api/Chapter. This vulnerability is fixed in 0.9.0.

Kavita is a cross platform reading server. Prior to 0.9.0, the ReaderController.GetImage endpoint is decorated with [AllowAnonymous], allowing completely unauthenticated access to page images from any chapter in any library. While the endpoint accepts an apiKey parameter, it is never validated. Since entity IDs are sequential integers, an unauthenticated attacker can trivially enumerate all content on the server. This vulnerability is fixed in 0.9.0.

Kavita is a cross platform reading server. Prior to 0.9.0.2, an Improper Token validation flaw permits a remote and unauthenticated threat actor to request a JWT for any user including admins given knowledge of their username. This vulnerability is fixed in 0.9.0.2.