Summary
The deleteProcess() action accepts a POST parameter tables[] containing arbitrary table names. These are passed directly to $forge->dropTable() without validating that the tables belong to the theme being deleted.
The deleteConfirm view correctly populates tables[] from the theme's own migration files, but the server-side deleteProcess does not verify the received values against those files. An authenticated admin can craft a POST request with arbitrary table names and drop any table in the database.
This is a real bug even within the admin trust model: the action should be scoped to the theme's own tables. The permission grants delete this theme's data", not "drop any table".
Details
Location
modules/Theme/Controllers/Theme.php :: deleteProcess() ~line 147
Vulnerable Code
public function deleteProcess(string $slug)
{
$themeName = $slug;
$activeTheme = setting('App.siteTheme');
if ($activeTheme === $themeName) {
return redirect()->route('templateSettings')...;
}
$tablesToDrop = $this->request->getPost('tables'); // ← user-supplied, unvalidated
if (!empty($tablesToDrop) && is_array($tablesToDrop)) {
$forge = \Config\Database::forge();
$db = \Config\Database::connect();
foreach ($tablesToDrop as $table) {
if ($db->tableExists($table)) {
$forge->dropTable($table, true); // ← no whitelist check
}
}
}
PoC
- Authenticate to the backend (any user with theme.delete permission)
- POST to
/backend/themes/delete-process/<any_non_active_theme_slug>
- Include
tables[]=<any_table> in POST body
- The named tables are dropped without validation
Impact
- Dropped
ci4ms_blog (confirmed in test)
- Dropped
ci4ms_users + ci4ms_auth_identities simultaneously — disables all authentication (confirmed)
- Any table in the database can be targeted
Additional note
Quick note on the design intent for deleteProcess — I noticed delete_confirm.php scopes the checkboxes to the theme's own migration files, and the CHANGELOG confirms the selective deletion was intentional (admins can choose which tables to keep). The server-side deleteProcess already has all the information it needs to validate the input — deleteConfirm derives the valid table set from the migration files, deleteProcess just needs to do the same before acting on the POST. Happy to clarify if useful.
References
Summary
The
deleteProcess()action accepts a POST parametertables[]containing arbitrary table names. These are passed directly to$forge->dropTable()without validating that the tables belong to the theme being deleted.The
deleteConfirmview correctly populatestables[]from the theme's own migration files, but the server-sidedeleteProcessdoes not verify the received values against those files. An authenticated admin can craft a POST request with arbitrary table names and drop any table in the database.This is a real bug even within the admin trust model: the action should be scoped to the theme's own tables. The permission grants delete this theme's data", not "drop any table".
Details
Location
modules/Theme/Controllers/Theme.php::deleteProcess()~line 147Vulnerable Code
PoC
/backend/themes/delete-process/<any_non_active_theme_slug>tables[]=<any_table>in POST bodyImpact
ci4ms_blog(confirmed in test)ci4ms_users+ci4ms_auth_identitiessimultaneously — disables all authentication (confirmed)Additional note
Quick note on the design intent for deleteProcess — I noticed delete_confirm.php scopes the checkboxes to the theme's own migration files, and the CHANGELOG confirms the selective deletion was intentional (admins can choose which tables to keep). The server-side deleteProcess already has all the information it needs to validate the input — deleteConfirm derives the valid table set from the migration files, deleteProcess just needs to do the same before acting on the POST. Happy to clarify if useful.
References