CVE-2026-61518: Improper Neutralization of Special Elements used in an SQL Command

ISPConfig contains an authenticated SQL injection vulnerability in the Remote API. The primary_id parameter passed to delete and update API methods is concatenated directly into SQL WHERE clauses without integer casting or parameterized query binding. The built-in SQL injection scanner does not block quote-free boolean payloads and does not reject requests in its default configuration. A remote API user holding any single low-privilege function permission can inject arbitrary SQL to delete or modify records across all tenants in the control panel database and extract arbitrary data via blind boolean inference, including password hashes and client records.