Rule Category

POLICY-OTHER --

Alert Message

POLICY-OTHER PyYAML Python object serialization attempt

Rule Explanation

This rule detects the attempted download of a YAML file that contains a serialized Python object by looking for the syntax used to create a new Python object. This rule is in response to the ability to run arbitrary code via the object deserialization process in PyYAML when loading untrusted YAML files without using a safe YAML load method.

What To Look For

This rule detects the attempted download of a YAML file that contains a serialized Python object.

Known Usage

No public information

False Positives

No known false positives

Contributors

Cisco Talos Intelligence Group

MITRE ATT&CK Framework

Tactic: Execution

Technique: Execution through Module Load

For reference, see the MITRE ATT&CK vulnerability types here: https://attack.mitre.org

Rule Vulnerability

N/A

Not Applicable

CVE Additional Information