was missing a nil check

db/schema.rb

@@ -11,7 +11,7 @@
 #
 # It's strongly recommended to check this file into your version control system.
 
-ActiveRecord::Schema.define(:version => 20130531144949) do
+ActiveRecord::Schema.define(:version => 20130604145732) do
 
   create_table "api_keys", :force => true do |t|
     t.text     "token"
@@ -440,6 +440,13 @@ ActiveRecord::Schema.define(:version => 20130531144949) do
     t.datetime "updated_at", :null => false
   end
 
+  create_table "task_sessions", :force => true do |t|
+    t.integer  "task_id",    :null => false
+    t.integer  "session_id", :null => false
+    t.datetime "created_at", :null => false
+    t.datetime "updated_at", :null => false
+  end
+
   create_table "tasks", :force => true do |t|
     t.integer  "workspace_id",                 :default => 1, :null => false
     t.string   "created_by"

lib/msf/core/db.rb

@@ -786,7 +786,7 @@ class DBManager
 		s = ::Mdm::Session.new(sess_data)
 		s.save!
 
-    if session.exploit_task and session.exploit_task.record
+    if session and session.exploit_task and session.exploit_task.record
       session_task =  session.exploit_task.record
       if session_task.class == Mdm::Task
         Mdm::TaskSession.create(:task => session_task, :session => s )