diff --git a/core/modules/ckeditor5/src/Controller/CKEditor5ImageController.php b/core/modules/ckeditor5/src/Controller/CKEditor5ImageController.php
index d7ef7f7e4e1..72d71ef54bf 100644
--- a/core/modules/ckeditor5/src/Controller/CKEditor5ImageController.php
+++ b/core/modules/ckeditor5/src/Controller/CKEditor5ImageController.php
@@ -210,6 +210,16 @@ public function upload(Request $request) {
     }
 
     $file->setFileUri($file_uri);
+    $violations = $file->validate();
+
+    // Remove violations of inaccessible fields as they cannot stem from our
+    // changes.
+    $violations->filterByFieldAccess();
+
+    if ($violations->count() > 0) {
+      throw new UnprocessableEntityHttpException($violations->__toString());
+    }
+
     $file->save();
 
     $this->lock->release($lock_id);
@@ -253,23 +263,7 @@ public function imageUploadEnabledAccess(Editor $editor) {
    *   The list of constraint violations, if any.
    */
   protected function validate(FileInterface $file, array $validators) {
-    $violations = $file->validate();
-
-    // Remove violations of inaccessible fields as they cannot stem from our
-    // changes.
-    $violations->filterByFieldAccess();
-
-    // Prevent validation of the URI field because the file validation handler
-    // expects it to have a schema, and it does not have one yet.
-    $fieldNames = $violations->getFieldNames();
-
-    // The filterByFields() method doesn't work with an empty array.
-    if ($fieldNames === ['uri']) {
-      $violations = new EntityConstraintViolationList($file);
-    }
-    else {
-      $violations->filterByFields(array_diff($fieldNames, ['uri']));
-    }
+    $violations = new EntityConstraintViolationList($file);
 
     // Validate the file based on the field definition configuration.
     $violations->addAll($this->fileValidator->validate($file, $validators));