Ghost CMS Admin API Dynamic Script Injection Attempt
This rule detects suspicious update requests to the Ghost CMS Admin API that indicate an attempt at dynamic script injection. It specifically looks for PUT requests to `/ghost/api/admin/posts/` containing markers associated with Base64 decoding (`atob(`) and dynamic DOM manipulation (`appendChild`, `createElement`), or specific strings (`ghost_once_footer_`, `btoa(a.origin)`) known to be used in the Ghost ClickFix attack chain. This activity suggests an attacker is attempting to inject malicious JavaScript into Ghost CMS content, potentially leveraging a vulnerability like CVE-2026-26980.
Microsoft Sentinel (KQL)
