Bug 671612: Send "X-Content-Type-Options: nosniff" with every response

Bugzilla/Attachment/PatchReader.pm

@@ -27,7 +27,6 @@ sub process_diff {
         $last_reader->sends_data_to(new PatchReader::DiffPrinter::raw());
         # Actually print out the patch.
         print $cgi->header(-type => 'text/plain',
-                           -x_content_type_options => "nosniff",
                            -expires => '+3M');
         disable_utf8();
         $reader->iterate_string('Attachment ' . $attachment->id, $attachment->data);
@@ -109,7 +108,6 @@ sub process_interdiff {
         $last_reader->sends_data_to(new PatchReader::DiffPrinter::raw());
         # Actually print out the patch.
         print $cgi->header(-type => 'text/plain',
-                           -x_content_type_options => "nosniff",
                            -expires => '+3M');
         disable_utf8();
     }

Bugzilla/CGI.pm

@@ -317,6 +317,10 @@ sub header {
     # and enforce the blocking (rather than the rewriting) mode.
     unshift(@_, '-x_xss_protection' => '1; mode=block');
 
+    # Add X-Content-Type-Options header to prevent browsers sniffing
+    # the MIME type away from the declared Content-Type.
+    unshift(@_, '-x_content_type_options' => 'nosniff');
+
     return $self->SUPER::header(@_) || "";
 }
 

attachment.cgi

@@ -385,8 +385,7 @@ sub view {
     }
     print $cgi->header(-type=>"$contenttype; name=\"$filename\"",
                        -content_disposition=> "$disposition; filename=\"$filename\"",
-                       -content_length => $attachment->datasize,
-                       -x_content_type_options => "nosniff");
+                       -content_length => $attachment->datasize);
     disable_utf8();
     print $attachment->data;
 }