PlexRipper is a cross-platform media downloader for Plex. PlexRipper’s open CORS policy allows attackers to gain sensitive information from PlexRipper by getting the user to access the attacker’s domain. This allows an attacking website to access the /api/PlexAccount endpoint and steal the user’s Plex login. This vulnerability is fixed in 0.24.0.
The product uses a web-client protection mechanism such as a Content Security Policy (CSP) or cross-domain policy file, but the policy includes untrusted domains with which the web client is allowed to communicate.
If a cross-domain policy file includes domains that should not be trusted, such as when using wildcards under a high-level domain, then the application could be attacked by these untrusted domains. In many cases, the attack can be launched without the victim even being aware of it.