CVE-2019-20477
CRITICALPyYAML 5.1-5.1.2 - Deserialization of Untrusted Data via Insufficient Class Restrictions
Title source: llmDescription
PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.
References (4)
Core 4
Core References
Release Notes, Third Party Advisory x_refsource_misc
https://github.com/yaml/pyyaml/blob/master/CHANGES
Exploit, Third Party Advisory, VDB Entry x_refsource_misc
https://www.exploit-db.com/download/47655
Mailing List, Third Party Advisory vendor-advisory
x_refsource_fedora
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/52N5XS73Z5S4ZN7I7R56ICCPCTKCUV4H/
Mailing List, Third Party Advisory vendor-advisory
x_refsource_fedora
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/33VBUY73AA6CTTYL3LRWHNFDULV7PFPN/
Scores
CVSS v3
9.8
EPSS
0.0503
EPSS Percentile
91.2%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Details
CWE
CWE-502
Status
published
Products (4)
fedoraproject/fedora
30
fedoraproject/fedora
31
pypi/pyyaml
5.1 - 5.2PyPI
pyyaml/pyyaml
5.1 - 5.1.2
Published
Feb 19, 2020
Tracked Since
Feb 18, 2026