Ghost CLI before 1.30.1 contains an IP spoofing vulnerability that allows unauthenticated remote attackers to bypass rate-limiting controls by manipulating the X-Forwarded-For header through a misconfigured Nginx configuration. Attackers can append attacker-controlled values to the header chain using the $proxyaddxforwardedfor directive to present an arbitrary IP address, circumventing Ghost's rate-limiting mechanisms on self-hosted instances.