CVE-2019-20477

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.

CVSS v3.0 9.8 CRITICAL
CVSS v2.0 7.5 HIGH

9.8^/10

CVSS v3.0 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

7.5^/10

CVSS v2.0 : HIGH

Vector : AV:N/AC:L/Au:N/C:P/I:P/A:P

Exploitability : 10.0 / Impact : 6.4

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://www.exploit-db.com/download/47655	Exploit Third Party Advisory VDB Entry
https://github.com/yaml/pyyaml/blob/master/CHANGES	Release Notes Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/52N5XS73Z5S4ZN7I7R56ICCPCTKCUV4H/	Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/33VBUY73AA6CTTYL3LRWHNFDULV7PFPN/	Mailing List Third Party Advisory

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Configurations

Configuration 1 (hide)

cpe:2.3:a:pyyaml:pyyaml:*:*:*:*:*:*:*:*

Configuration 2 (hide)

OR	cpe:2.3:o:fedoraproject:fedora:30:::::::*
	cpe:2.3:o:fedoraproject:fedora:31:::::::*

Information

Published : 2020-02-18 20:15

Updated : 2022-01-01 11:38

NVD link : CVE-2019-20477

Mitre link : CVE-2019-20477

JSON object : View

CWE

CWE-502

Deserialization of Untrusted Data

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Products Affected

pyyaml

pyyaml

fedoraproject

fedora

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