Plex Media Server before 1.43.3.10861 allows an admin user to write arbitrary files that may be executed on load. The preference TranscoderH264Options is appended verbatim to x264's option string on every transcode. At startup, all .so files are run without signature, execute bit, or symbol checks.
Plex Media Server before 1.43.3.10861 allows an authenticated user to request arbitrary internal or external addresses via the '/video/:/transcode/universal' path parameter.
Plex Media Server before 1.43.3.10861 does not correctly neutralize URL values included in 'searchOne,' allowing an attacker to call other plugins' functions and supply their own parameters.
Plex Media Server before 1.43.3.10861 allows SSRF via '/player/timeline'. An attacker using any X-Plex-Token value can include a full URL in the 'protocol' parameter and force the Plex server to POST to the attacker's chosen destination.
Plex Media Server before 1.43.3.10861 builds a file path from the url parameter without checking it for ../ sequences, allowing path traversal via '/system/agents/media/get'. A remote attacker with a valid session token could read any file that the target user can access. This access includes the PlexOnlineToken, which grants control of the Plex account and server. A LAN-adjacent attacker with a client-supplied X-Forwarded-For header could exploit the same issue.
In the plex.tv backend for Plex Media Server (PMS) through 2025-12-31, a non-server device token can retrieve share tokens (intended for unrelated access) via a sharedservers endpoint.
In the plex.tv backend for Plex Media Server (PMS) through 2025-12-31, a non-server device token can retrieve other tokens (intended for unrelated access) via clients.plex.tv/devices.xml.
In Plex Media Server (PMS) through 1.42.2.10156, ability to access /myplex/account with a device token is not properly aligned with whether the device is currently associated with an account.
Plex Media Server (PMS) through 1.42.2.10156 allows retrieval of a permanent access token via a /myplex/account call with a transient access token.
Plex Media Server (PMS) 1.41.7.x through 1.42.0.x before 1.42.1 is affected by incorrect resource transfer between spheres because /myplex/account provides the credentials of the server owner (and a /api/resources call reveals other servers accessible by that server owner).