diff --git a/lib/vagrant/box_collection.rb b/lib/vagrant/box_collection.rb
index 4544d7b14..2e9db8c54 100644
--- a/lib/vagrant/box_collection.rb
+++ b/lib/vagrant/box_collection.rb
@@ -96,69 +96,71 @@ module Vagrant
 
       # Create a temporary directory since we're not sure at this point if
       # the box we're unpackaging already exists (if no provider was given)
-      temp_dir = Pathname.new(Dir.mktmpdir(TEMP_PREFIX))
+      with_temp_dir do |temp_dir|
+        # Extract the box into a temporary directory.
+        @logger.debug("Unpacking box into temporary directory: #{temp_dir}")
+        result = Util::Subprocess.execute(
+          "bsdtar", "-v", "-x", "-m", "-C", temp_dir.to_s, "-f", path.to_s)
+        raise Errors::BoxUnpackageFailure, :output => result.stderr.to_s if result.exit_code != 0
 
-      # Extract the box into a temporary directory.
-      @logger.debug("Unpacking box into temporary directory: #{temp_dir}")
-      result = Util::Subprocess.execute(
-        "bsdtar", "-v", "-x", "-m", "-C", temp_dir.to_s, "-f", path.to_s)
-      raise Errors::BoxUnpackageFailure, :output => result.stderr.to_s if result.exit_code != 0
-
-      # If we get a V1 box, we want to update it in place
-      if v1_box?(temp_dir)
-        @logger.debug("Added box is a V1 box. Upgrading in place.")
-        temp_dir = v1_upgrade(temp_dir)
-      end
-
-      # Get an instance of the box we just added before it is finalized
-      # in the system so we can inspect and use its metadata.
-      box = Box.new(name, provider, temp_dir)
-
-      # Get the provider, since we'll need that to at the least add it
-      # to the system or check that it matches what is given to us.
-      box_provider = box.metadata["provider"]
-
-      if provider
-        # Verify that the given provider matches what the box has.
-        if box_provider.to_sym != provider
-          @logger.error("Added box provider doesnt match expected: #{box_provider}")
-          raise Errors::BoxProviderDoesntMatch, :expected => provider, :actual => box_provider
+        # If we get a V1 box, we want to update it in place
+        if v1_box?(temp_dir)
+          @logger.debug("Added box is a V1 box. Upgrading in place.")
+          temp_dir = v1_upgrade(temp_dir)
         end
-      else
-        # We weren't given a provider, so store this one.
-        provider = box_provider.to_sym
 
-        # Verify the box doesn't already exist
-        check_box_exists.call(provider)
+        # We re-wrap ourselves in the safety net in case we upgraded.
+        # If we didn't upgrade, then this is still safe because the
+        # helper will only delete the directory if it exists
+        with_temp_dir(temp_dir) do |final_temp_dir|
+          # Get an instance of the box we just added before it is finalized
+          # in the system so we can inspect and use its metadata.
+          box = Box.new(name, provider, final_temp_dir)
+
+          # Get the provider, since we'll need that to at the least add it
+          # to the system or check that it matches what is given to us.
+          box_provider = box.metadata["provider"]
+
+          if provider
+            # Verify that the given provider matches what the box has.
+            if box_provider.to_sym != provider
+              @logger.error("Added box provider doesnt match expected: #{box_provider}")
+              raise Errors::BoxProviderDoesntMatch, :expected => provider, :actual => box_provider
+            end
+          else
+            # We weren't given a provider, so store this one.
+            provider = box_provider.to_sym
+
+            # Verify the box doesn't already exist
+            check_box_exists.call(provider)
+          end
+
+          # Create the directory for this box, not including the provider
+          box_dir = @directory.join(name)
+          box_dir.mkpath
+          @logger.debug("Box directory: #{box_dir}")
+
+          # This is the final directory we'll move it to
+          final_dir = box_dir.join(provider.to_s)
+          if final_dir.exist?
+            @logger.debug("Removing existing provider directory...")
+            final_dir.rmtree
+          end
+
+          # Move to final destination
+          final_dir.mkpath
+
+          # Go through each child and copy them one-by-one. This avoids
+          # an issue where on Windows cross-device directory copies are
+          # failing for some reason. [GH-1424]
+          final_temp_dir.children(true).each do |f|
+            destination = final_dir.join(f.basename)
+            @logger.debug("Moving: #{f} => #{destination}")
+            FileUtils.mv(f, destination)
+          end
+        end
       end
 
-      # Create the directory for this box, not including the provider
-      box_dir = @directory.join(name)
-      box_dir.mkpath
-      @logger.debug("Box directory: #{box_dir}")
-
-      # This is the final directory we'll move it to
-      final_dir = box_dir.join(provider.to_s)
-      if final_dir.exist?
-        @logger.debug("Removing existing provider directory...")
-        final_dir.rmtree
-      end
-
-      # Move to final destination
-      final_dir.mkpath
-
-      # Go through each child and copy them one-by-one. This avoids
-      # an issue where on Windows cross-device directory copies are
-      # failing for some reason. [GH-1424]
-      temp_dir.children(true).each do |f|
-        destination = final_dir.join(f.basename)
-        @logger.debug("Moving: #{f} => #{destination}")
-        FileUtils.mv(f, destination)
-      end
-
-      # Remove the temporary directory
-      temp_dir.rmtree
-
       # Return the box
       find(name, provider)
     end
@@ -324,5 +326,19 @@ module Vagrant
       # Return the temporary directory
       temp_dir
     end
+
+    # This is a helper that makes sure that our temporary directories
+    # are cleaned up no matter what.
+    #
+    # @param [String] dir Path to a temporary directory
+    # @return [Object] The result of whatever the yield is
+    def with_temp_dir(dir=nil)
+      dir ||= Dir.mktmpdir("vagrant-")
+      dir = Pathname.new(dir)
+
+      yield dir
+    ensure
+      dir.rmtree if dir.exist?
+    end
   end
 end