A vulnerability was discovered in the PyYAML library in versions before 5.4, where it is susceptible to arbitrary code execution when it processes untrusted YAML files through the full_load method or with the FullLoader loader. Applications that use the library to process untrusted input may be vulnerable to this flaw. This flaw allows an attacker to execute arbitrary code on the system by abusing the python/object/new constructor. This flaw is due to an incomplete fix for CVE-2020-1747.
CVE-2020-14343 - Critical Severity Vulnerability
Vulnerable Library - PyYAML-3.13.tar.gz
YAML parser and emitter for Python
Library home page: https://files.pythonhosted.org/packages/9e/a3/1d13970c3f36777c583f136c136f804d70f500168edc1edea6daa7200769/PyYAML-3.13.tar.gz
Path to dependency file: /requirements.txt
Path to vulnerable library: /requirements.txt
Dependency Hierarchy: - :x: **PyYAML-3.13.tar.gz** (Vulnerable Library)
Found in base branch: main
Vulnerability Details
A vulnerability was discovered in the PyYAML library in versions before 5.4, where it is susceptible to arbitrary code execution when it processes untrusted YAML files through the full_load method or with the FullLoader loader. Applications that use the library to process untrusted input may be vulnerable to this flaw. This flaw allows an attacker to execute arbitrary code on the system by abusing the python/object/new constructor. This flaw is due to an incomplete fix for CVE-2020-1747.
Publish Date: 2021-02-09
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
For more information on CVSS3 Scores, click here.Suggested Fix
Type: Upgrade version
Origin: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-14343
Release Date: 2021-02-09
Fix Resolution: PyYAML - 5.4
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