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vulnerability

FreeBSD: VID-aae8fecf-888e-11ea-9714-08002718de91 (CVE-2020-1747): py-yaml -- FullLoader (still) exploitable for arbitrary command execution

Severity
10
CVSS
(AV:N/AC:L/Au:N/C:C/I:C/A:C)
Published
Apr 27, 2020
Added
Apr 28, 2020
Modified
Jun 15, 2026

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.

Solutions

freebsd-upgrade-package-py27-yamlfreebsd-upgrade-package-py35-yamlfreebsd-upgrade-package-py36-yamlfreebsd-upgrade-package-py37-yamlfreebsd-upgrade-package-py38-yaml
Title
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