YAML Injection
A security vulnerability where malicious input is injected into YAML parsers, leading to code execution or data manipulation.
Understanding YAML Injection
YAML (Yet Another Markup Language) is widely used for configuration files and data serialization. YAML Injection occurs when untrusted input is parsed in an unsafe manner, allowing attackers to execute arbitrary code, access system files, or modify configurations.
Common Security Risks in YAML Injection
Remote Code Execution (RCE)
If YAML is parsed with unsafe deserialization, attackers can inject malicious payloads leading to code execution.
Sensitive Data Exposure
Poorly secured YAML configurations may expose database credentials, API keys, or system secrets.
Denial-of-Service (DoS) Attacks
Large or malformed YAML payloads can crash applications by consuming excessive resources.
Path Traversal and File Manipulation
Attackers can exploit YAML parsing to read, modify, or delete files on the server.
Mitigation and Security Best Practices
Use Safe YAML Parsers – Libraries like ruamel.yaml (Python) and js-yaml (JavaScript) support safe loading.
Validate and Sanitize Input – Ensure all user-provided YAML content is sanitized before processing.
Restrict File Access – Use least privilege principles to prevent unauthorized file modifications.
Disable Unnecessary Features – Disable arbitrary object deserialization to prevent RCE vulnerabilities.
Monitor Logs for Suspicious Activity – Track YAML-related errors and anomalies in application logs.