CraftCMS's `ElementSearchController` Affected by Blind SQL Injection

The ElementSearchController::actionSearch() endpoint is missing the unset() protection that was added to ElementIndexesController in GHSA-2453-mppf-46cj.

The exact same SQL injection vulnerability (including criteria[orderBy], the original advisory vector) works on this controller because the fix was never applied to it.

Any authenticated control panel user (no admin required) can inject arbitrary SQL via criteria[where], criteria[orderBy], or other query properties, and extract the full database contents via boolean-based blind injection.

Users should update to the patched 5.9.9 release to mitigate the issue.