diff --git a/app/controllers/api/v1/apps_controller.rb b/app/controllers/api/v1/apps_controller.rb
index ca9dd0b7eea..2ec7280af05 100644
--- a/app/controllers/api/v1/apps_controller.rb
+++ b/app/controllers/api/v1/apps_controller.rb
@@ -4,6 +4,12 @@ class Api::V1::AppsController < ApiController
   respond_to :json
 
   def create
-    @app = Doorkeeper::Application.create!(name: params[:client_name], redirect_uri: params[:redirect_uris], scopes: (params[:scopes] || Doorkeeper.configuration.default_scopes), website: params[:website])
+    @app = Doorkeeper::Application.create!(name: app_params[:client_name], redirect_uri: app_params[:redirect_uris], scopes: (app_params[:scopes] || Doorkeeper.configuration.default_scopes), website: app_params[:website])
+  end
+
+  private
+
+  def app_params
+    params.permit(:client_name, :redirect_uris, :scopes, :website)
   end
 end
diff --git a/app/controllers/api/v1/follows_controller.rb b/app/controllers/api/v1/follows_controller.rb
index c22dacbaab7..7c0f44f0383 100644
--- a/app/controllers/api/v1/follows_controller.rb
+++ b/app/controllers/api/v1/follows_controller.rb
@@ -7,7 +7,7 @@ class Api::V1::FollowsController < ApiController
   respond_to :json
 
   def create
-    raise ActiveRecord::RecordNotFound if params[:uri].blank?
+    raise ActiveRecord::RecordNotFound if follow_params[:uri].blank?
 
     @account = FollowService.new.call(current_user.account, target_uri).try(:target_account)
     render action: :show
@@ -16,6 +16,10 @@ class Api::V1::FollowsController < ApiController
   private
 
   def target_uri
-    params[:uri].strip.gsub(/\A@/, '')
+    follow_params[:uri].strip.gsub(/\A@/, '')
+  end
+
+  def follow_params
+    params.permit(:uri)
   end
 end
diff --git a/app/controllers/api/v1/media_controller.rb b/app/controllers/api/v1/media_controller.rb
index f8139ade771..aed3578d7e8 100644
--- a/app/controllers/api/v1/media_controller.rb
+++ b/app/controllers/api/v1/media_controller.rb
@@ -10,10 +10,16 @@ class Api::V1::MediaController < ApiController
   respond_to :json
 
   def create
-    @media = MediaAttachment.create!(account: current_user.account, file: params[:file])
+    @media = MediaAttachment.create!(account: current_user.account, file: media_params[:file])
   rescue Paperclip::Errors::NotIdentifiedByImageMagickError
     render json: { error: 'File type of uploaded media could not be verified' }, status: 422
   rescue Paperclip::Error
     render json: { error: 'Error processing thumbnail for uploaded media' }, status: 500
   end
+
+  private
+
+  def media_params
+    params.permit(:file)
+  end
 end
diff --git a/app/controllers/api/v1/reports_controller.rb b/app/controllers/api/v1/reports_controller.rb
index 46bdddbc148..f83c573cb5f 100644
--- a/app/controllers/api/v1/reports_controller.rb
+++ b/app/controllers/api/v1/reports_controller.rb
@@ -12,13 +12,19 @@ class Api::V1::ReportsController < ApiController
   end
 
   def create
-    status_ids = params[:status_ids].is_a?(Enumerable) ? params[:status_ids] : [params[:status_ids]]
+    status_ids = report_params[:status_ids].is_a?(Enumerable) ? report_params[:status_ids] : [report_params[:status_ids]]
 
     @report = Report.create!(account: current_account,
-                             target_account: Account.find(params[:account_id]),
+                             target_account: Account.find(report_params[:account_id]),
                              status_ids: Status.find(status_ids).pluck(:id),
-                             comment: params[:comment])
+                             comment: report_params[:comment])
 
     render :show
   end
+
+  private
+
+  def report_params
+    params.permit(:account_id, :comment, status_ids: [])
+  end
 end
diff --git a/app/controllers/api/v1/statuses_controller.rb b/app/controllers/api/v1/statuses_controller.rb
index 024258c0e15..4ece7e70281 100644
--- a/app/controllers/api/v1/statuses_controller.rb
+++ b/app/controllers/api/v1/statuses_controller.rb
@@ -62,11 +62,11 @@ class Api::V1::StatusesController < ApiController
   end
 
   def create
-    @status = PostStatusService.new.call(current_user.account, params[:status], params[:in_reply_to_id].blank? ? nil : Status.find(params[:in_reply_to_id]), media_ids: params[:media_ids],
-                                                                                                                                                             sensitive: params[:sensitive],
-                                                                                                                                                             spoiler_text: params[:spoiler_text],
-                                                                                                                                                             visibility: params[:visibility],
-                                                                                                                                                             application: doorkeeper_token.application)
+    @status = PostStatusService.new.call(current_user.account, status_params[:status], status_params[:in_reply_to_id].blank? ? nil : Status.find(status_params[:in_reply_to_id]), media_ids: status_params[:media_ids],
+                                                                                                                                                                                  sensitive: status_params[:sensitive],
+                                                                                                                                                                                  spoiler_text: status_params[:spoiler_text],
+                                                                                                                                                                                  visibility: status_params[:visibility],
+                                                                                                                                                                                  application: doorkeeper_token.application)
     render action: :show
   end
 
@@ -111,4 +111,8 @@ class Api::V1::StatusesController < ApiController
     @status = Status.find(params[:id])
     raise ActiveRecord::RecordNotFound unless @status.permitted?(current_account)
   end
+
+  def status_params
+    params.permit(:status, :in_reply_to_id, :sensitive, :spoiler_text, :visibility, media_ids: [])
+  end
 end
diff --git a/app/models/status.rb b/app/models/status.rb
index 81b26fd1459..daf1285720f 100644
--- a/app/models/status.rb
+++ b/app/models/status.rb
@@ -188,7 +188,7 @@ class Status < ApplicationRecord
   end
 
   before_validation do
-    text.strip!
+    text&.strip!
     spoiler_text&.strip!
 
     self.reply                  = !(in_reply_to_id.nil? && thread.nil?) unless reply