determine most precise filter

drop back to our most precise level of filtering

MS-2325

lib/msf/core/exploit/auto_target.rb

@@ -15,9 +15,7 @@ module Msf
       return nil unless auto_target?
       host_record = target_host
       return nil if host_record.nil?
-      filtered_by_family = filter_by_os_family(host_record)
-      filtered_by_name   = filter_by_os_name(filtered_by_family, host_record)
-      filtered_by_sp     = filter_by_os_sp(filtered_by_name,host_record)
+
     end
 
     def target_host
@@ -27,6 +25,17 @@ module Msf
       current_workspace.hosts.where(address: rhost).first
     end
 
+    def filter_by_os(host_record)
+      filtered_by_family = filter_by_os_family(host_record)
+      filtered_by_name   = filter_by_os_name(filtered_by_family, host_record)
+      # If Filtering by name gave us no results, then we reset back to the family filter group
+      filtered_by_name   = filtered_by_family if filtered_by_name.empty?
+      filtered_by_sp     = filter_by_os_sp(filtered_by_name,host_record)
+      # If Filtering by SP was a bust, revert back one level
+      filtered_by_sp     = filtered_by_name if filtered_by_sp.empty?
+      filtered_by_sp
+    end
+
     def filter_by_os_family(host_record)
       return [] if host_record.os_family.blank?
       filtered_targets = targets.collect do |target|

spec/lib/msf/core/exploit/auto_target_spec.rb

@@ -116,6 +116,16 @@ RSpec.describe Msf::Exploit::AutoTarget do
 
     end
 
+    context '#filter_by_os' do
+      it 'should return an array of matching targets' do
+        expect(windows_exploit.filter_by_os(windows_xp_sp1_host)).to eq [xp_targets[0]]
+      end
+
+      it 'should fall back to previous filter levels if a more strict filter did not return results' do
+        expect(windows_exploit.filter_by_os(windows_xp_host)).to eq xp_targets
+      end
+    end
+
   end