The Smart Popup by Supsystic WordPress plugin before 2.0.2 does not prevent template-injection payloads from being stored in a popup text block and later evaluated by its template engine, because the filter meant to strip template delimiters runs before a decoding step that reconstructs them, allowing an authenticated administrator to execute arbitrary template expressions server-side and read PHP constants such as the site's database credentials and authentication keys.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
High
Admin privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
None
No data modification
Availability
None
No disruption
CVSS Vector v3.1