Validation of the authentication adapter app ID for Facebook and Spotify may be circumvented.
This fixes a vulnerability that affects configurations which allow users to authenticate using the Parse Server authentication adapter for Facebook or Spotify and where the server-side authentication adapter configuration
appIds is set as a string (e.g.
abc) instead of an array of strings (e.g.
["abc"]). The vulnerability makes it possible to authenticate requests which are coming from a Facebook or Spotify app with a different app ID than the one specified in the
Both adapters still validate the access token with the respective authentication provider. An app ID is automatically assigned by the authentication provider. For this vulnerability to be exploited, an attacker would have to be assigned an app ID by the authentication provider which is a sub-set of the server-side configured app ID.
The documentation did not explicitly specify that the parameter
appIds must be set as an array of strings and setting a string also worked. Therefore, there is a possibility that there are deployments where
appIds is set as a string, making them vulnerable.
The fix makes Parse Server check the type of the value set for
appIds and throws an error if the value is not an array.
No known workarounds.