Make changes more precise [ruby#424]

Author: marcandre

CHANGES.md

@@ -1,7 +1,8 @@
 # Changes
 
 ## 2019-12-11 (2.3.0)
- * Fix default of `create_additions` to always be false [CVE-2020-10663]
+ * Fix default of `create_additions` to always be false for `JSON(user_input)`
+   and `JSON.parse(user_input, nil)` [CVE-2020-10663]
  * Fix passing args all #to_json in json/add/*.
  * Fix encoding issues
  * Fix issues of keyword vs positional parameter