XWiki OIDC Authenticator vulnerable to bypassing OpenID login by providing a custom provider
ImpactEven if a wiki has an OpenID provider configured through its xwiki.properties, it is possible to provide a third party provider by providing its details through request parameters. One can then bypass the XWiki authentication altogether by specifying its own provider through the oidc.endpoint.* request parameters (or by using an XWiki-based OpenID provider with oidc.xwikiprovider.With the same approach, one could also provide a specific group mapping through oidc.groups.mapping that would make his user automatically part of the XWikiAdminGroupPatchesPatched in version 1.29.1.WorkaroundsThere is no workaround, an upgrade of the authenticator is required.Referenceshttps://jira.xwiki.org/browse/OIDC-118For more informationIf you have any questions or comments about this advisory:Open an issue in Jira XWikiEmail us at our security mailing list