CVE-2019-20477
Deserialization of Untrusted Data in PyYAML
9.8
CRITICAL
CVSS 3.1
EPSS 0.42%
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.
How to fix CVE-2019-20477
To remediate CVE-2019-20477, upgrade the affected package to a fixed version below.
- —upgrade to 5.2-1 or later
- —upgrade to 5.2 or later
- —upgrade to 5.2b1 or later
Is CVE-2019-20477 being exploited?
Low — EPSS is 0.4%, meaning exploitation activity has not been observed at scale.
Affected packages (3)
- from 0, < 5.2-1
- >= 5.1, < 5.2
- >= 5.1, < 5.2b1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N |
| osv | CVSS 3.1 | CRITICAL9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |