Multiple format string vulnerabilities in the error reporting functionality in the YAML::LibYAML (aka YAML-LibYAML and perl-YAML-LibYAML) module 0.38 for Perl allow remote attackers to cause a denial of service (process crash) via format string specifiers in a (1) YAML stream to the Load function, (2) YAML node to the load_node function, (3) YAML mapping to the load_mapping function, or (4) YAML sequence to the load_sequence function.