CVE-2019-20477

Public Exploit

Description

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.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.80% Top 30%
Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/yaml/pyyaml/blob/master/CHANGES third party advisory release notes
https://www.exploit-db.com/download/47655 third party advisory vdb entry exploit
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/52N5XS73Z5S4ZN7I7R56ICCPCTKCUV4H/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/33VBUY73AA6CTTYL3LRWHNFDULV7PFPN/ vendor advisory

Frequently Asked Questions

What is the severity of CVE-2019-20477?
CVE-2019-20477 has been scored as a critical severity vulnerability.
How to fix CVE-2019-20477?
To fix CVE-2019-20477, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2019-20477 being actively exploited in the wild?
It is possible that CVE-2019-20477 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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