All vulnerabilities
CVE-2020-1747
Improper Input Validation in PyYAML
Description
A vulnerability was discovered in the PyYAML library in versions before 5.3.1, 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. An attacker could use this flaw to execute arbitrary code on the system by abusing the python/object/new constructor.
Patch Available
Fix available through Seal Security.
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Fix without upgrading
Score
9.8
Severity
Critical
Ecosystem
Python
Publish Date
March 24, 2020
Modified Date
May 4, 2026
Score Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected Versions

