YAML-LibYAML prior to 0.903.0 for Perl uses 2-args open, allowing existing files to be modified

YAML-LibYAML prior to 0.903.0 for Perl uses 2-args open, allowing existing files to be modified

YAML::Syck versions before 1.36 for Perl has missing null-terminators which causes out-of-bounds read and potential information disclosure

Missing null terminators in token.c leads to but-of-bounds read which allows adjacent variable to be read

The issue is seen with complex YAML files with a hash of all keys and empty values.  There is no indication that the issue leads to accessing memory outside that allocated to the module.

Using snakeYAML to parse untrusted YAML files may be vulnerable to Denial of Service attacks (DOS). If the parser is running on user supplied input, an attacker may supply content that causes the parser to crash by stackoverflow.

https://bitbucket.org/snakeyaml/snakeyaml/issues/530/stackoverflow-oss-fuzz-47039 https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=47039