CVE-2022-43693: Concrete CMS vulnerable to Cross-site Request Forgery

The vulnerability stems from missing state parameter validation in the OAuth flow. The patch notes explicitly mention adding state parameter handling, which is a critical CSRF protection mechanism in OAuth2. The AbstractService class would logically contain authorization handling code, and ExternalUserProvider would handle authentication validation - both would require state parameter validation to prevent CSRF. The high confidence comes from: 1) Official patch notes specifically mentioning state parameter addition 2) Standard OAuth2 security requirements 3) Concrete CMS's architecture patterns for authentication handling.