Ghost 3.20.2 before 6.51.0 SSRF via image-size fetch

Ghost versions from 3.20.2 before 6.51.0 contain a server-side request forgery vulnerability in image dimension refetching that allows authenticated staff users to trigger outbound HTTP requests to arbitrary URLs. Attackers can point image cards at attacker-controlled hosts or internal network endpoints to access metadata services and internal resources unavailable from the public internet.