The REXML gem before 3.2.5 in Ruby before 2.6.7, 2.7.x before 2.7.3, and 3.x before 3.0.1 does not properly address XML round-trip issues. An incorrect document can be produced after parsing and serializing.
{ "binaries": [ { "binary_version": "2.3.1-2~ubuntu16.04.16", "binary_name": "libruby2.3" }, { "binary_version": "2.3.1-2~ubuntu16.04.16", "binary_name": "ruby2.3" }, { "binary_version": "2.3.1-2~ubuntu16.04.16", "binary_name": "ruby2.3-dev" }, { "binary_version": "2.3.1-2~ubuntu16.04.16", "binary_name": "ruby2.3-tcltk" } ], "availability": "No subscription required" }