In PyYAML before 5.1, the yaml.load() API could execute arbitrary code if used with untrusted data. The load() function has been deprecated in version 5.1 and the 'UnsafeLoader' has been introduced for backward compatibility with the function.

The function "Token& Scanner::peek" in scanner.cpp in yaml-cpp 0.5.3 and earlier allows remote attackers to cause a denial of service (assertion failure and application exit) via a '!2' string.

The SingleDocParser::HandleNode function in yaml-cpp (aka LibYaml-C++) 0.5.3 allows remote attackers to cause a denial of service (stack consumption and application crash) via a crafted YAML file.

scanner.c in LibYAML 0.1.5 and 0.1.6, as used in the YAML-LibYAML (aka YAML-XS) module for Perl, allows context-dependent attackers to cause a denial of service (assertion failure and crash) via vectors involving line-wrapping.

Heap-based buffer overflow in the yaml_parser_scan_uri_escapes function in LibYAML before 0.1.6 allows context-dependent attackers to execute arbitrary code via a long sequence of percent-encoded characters in a URI in a YAML file.

The yaml_parser_scan_tag_uri function in scanner.c in LibYAML before 0.1.5 performs an incorrect cast, which allows remote attackers to cause a denial of service (application crash) and possibly execute arbitrary code via crafted tags in a YAML document, which triggers a heap-based buffer overflow.

The JS-YAML module before 2.0.5 for Node.js parses input without properly considering the unsafe !!js/function tag, which allows remote attackers to execute arbitrary code via a crafted string that triggers an eval operation.

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.