Vulnerable Library - PyYAML-5.3.1.tar.gz

YAML parser and emitter for Python

Library home page: https://files.pythonhosted.org/packages/64/c2/b80047c7ac2478f9501676c988a5411ed5572f35d1beff9cae07d321512c/PyYAML-5.3.1.tar.gz

Path to dependency file: python_exercism/requirements.txt

Path to vulnerable library: python_exercism/requirements.txt

Dependency Hierarchy:

• pre_commit-1.21.0-py2.py3-none-any.whl (Root Library)
  • aspy.yaml-1.3.0-py2.py3-none-any.whl
    • ❌ PyYAML-5.3.1.tar.gz (Vulnerable Library)

Found in HEAD commit: f0061ffb2429e8c0a8fbf836928c52fe792d53e1

Found in base branch: master

Vulnerability Details

A vulnerability was discovered in the PyYAML library in all versions, where it is susceptible to arbitrary code execution when it processes untrusted YAML files through the full_load method or with the FullLoader loader. .load() defaults to using FullLoader and FullLoader is still vulnerable to RCE when run on untrusted input. Applications that use the library to process untrusted input may be vulnerable to this flaw. An attacker could use this flaw to execute arbitrary code on the system by abusing the python/object/new constructor.
The fix for CVE-2020-1747 was not enough to fix this issue.

Publish Date: 2020-07-21

URL: CVE-2020-14343

CVSS 3 Score Details (9.8)

Base Score Metrics:

• Exploitability Metrics:
  • Attack Vector: Network
  • Attack Complexity: Low
  • Privileges Required: None
  • User Interaction: None
  • Scope: Unchanged
• Impact Metrics:
  • Confidentiality Impact: High
  • Integrity Impact: High
  • Availability Impact: High