diff --git a/Library/Homebrew/download_strategy.rb b/Library/Homebrew/download_strategy.rb
index a70285ec56..7964497a79 100644
--- a/Library/Homebrew/download_strategy.rb
+++ b/Library/Homebrew/download_strategy.rb
@@ -483,7 +483,13 @@ class CurlDownloadStrategy < AbstractFileDownloadStrategy
 
       if (filename_with_encoding = content_disposition.parameters["filename*"])
         encoding, encoded_filename = filename_with_encoding.split("''", 2)
-        filename = URI.decode_www_form_component(encoded_filename).encode(encoding) if encoding && encoded_filename
+        # If the `filename*` has incorrectly added double quotes, e.g.
+        #   content-disposition: attachment; filename="myapp-1.2.3.pkg"; filename*=UTF-8''"myapp-1.2.3.pkg"
+        # Then the encoded_filename will come back as the empty string, in which case we should fall back to the
+        # `filename` parameter.
+        if encoding && encoded_filename.present?
+          filename = URI.decode_www_form_component(encoded_filename).encode(encoding)
+        end
       end
 
       # Servers may include '/' in their Content-Disposition filename header. Take only the basename of this, because: