diff --git a/app/models/attachment.rb b/app/models/attachment.rb
index 91ea010789..b32b6e9b60 100644
--- a/app/models/attachment.rb
+++ b/app/models/attachment.rb
@@ -81,7 +81,9 @@ class Attachment < ActiveRecord::Base
   end
 
   def content_disposition
-    inlineable? ? "inline" : "attachment; filename=#{self[:file]}"
+    # Do not use filename with attachment as this may break for Unicode files
+    # specifically when using S3 for attachments.
+    inlineable? ? "inline" : "attachment"
   end
 
   def visible?(user = User.current)
diff --git a/spec/models/attachment_spec.rb b/spec/models/attachment_spec.rb
index 62ffddd949..a7e85be1ae 100644
--- a/spec/models/attachment_spec.rb
+++ b/spec/models/attachment_spec.rb
@@ -290,8 +290,8 @@ describe Attachment, type: :model do
       before { binary_attachment.save! }
 
       it "should make S3 use content_disposition 'attachment; filename=...'" do
-        expect(binary_attachment.content_disposition).to eq "attachment; filename=textfile.txt.gz"
-        expect(binary_attachment.external_url.to_s).to include "response-content-disposition=attachment%3B%20filename%3Dtextfile.txt.gz"
+        expect(binary_attachment.content_disposition).to eq "attachment"
+        expect(binary_attachment.external_url.to_s).to include "response-content-disposition=attachment"
       end
     end
   end
diff --git a/spec/requests/api/v3/attachments/attachment_resource_shared_examples.rb b/spec/requests/api/v3/attachments/attachment_resource_shared_examples.rb
index b65411c7b4..ccace9fe91 100644
--- a/spec/requests/api/v3/attachments/attachment_resource_shared_examples.rb
+++ b/spec/requests/api/v3/attachments/attachment_resource_shared_examples.rb
@@ -294,7 +294,7 @@ shared_examples 'an APIv3 attachment resource', type: :request, content_type: :j
       context 'for a local binary file' do
         it_behaves_like 'for a local file' do
           let(:mock_file) { FileHelpers.mock_uploaded_file name: 'foobar.dat', content_type: "application/octet-stream" }
-          let(:content_disposition) { "attachment; filename=#{mock_file.original_filename}" }
+          let(:content_disposition) { "attachment" }
         end
       end