YAML injection is a critical security vulnerability that can occur when processing YAML data from untrusted sources. It's similar to SQL injection but targets YAML parsers instead of databases.
YAML injection exploits the way YAML parsers handle input. When malicious YAML content is processed without proper sanitization, it can lead to unauthorized code execution or data manipulation.
Attackers craft specially formatted YAML strings that, when parsed, can execute arbitrary code or access sensitive information. This vulnerability often arises from the use of unsafe YAML loading functions.
Consider this vulnerable Python code using PyYAML:
import yaml
user_input = "!!python/object/apply:os.system ['ls -l']"
data = yaml.load(user_input)
This code allows arbitrary command execution through YAML input.
To mitigate YAML injection risks:
yaml.safe_load()
in Python)
import yaml
user_input = "!!python/object/apply:os.system ['ls -l']"
data = yaml.safe_load(user_input)
# This will raise a YAMLError instead of executing the command
YAML injection can lead to severe security breaches, including:
To enhance YAML security in your applications:
Understanding these related topics can help improve overall YAML security:
By implementing these security measures and staying informed about potential vulnerabilities, developers can significantly reduce the risk of YAML injection attacks in their applications.