The nori gem 2.0.x before 2.0.2, 1.1.x before 1.1.4, and 1.0.x before 1.0.3 for Ruby does not properly restrict casts of string values, which allows remote attackers to conduct object-injection attacks and execute arbitrary code, or cause a denial of service (memory and CPU consumption) involving nested XML entity references, by leveraging Action Pack support for (1) YAML type conversion or (2) Symbol type conversion, a similar vulnerability to CVE-2013-0156.