VulnerabilityModified
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.
CRITICAL 9.8EPSS 5.16%
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (5.16%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a 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.
- CVSS 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 5.16% probability · 92th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-502
- Affected
- pyyaml/pyyaml · fedoraproject/fedora
- Source
- cve@mitre.org
References
- https://github.com/yaml/pyyaml/blob/master/CHANGESRelease Notes, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/33VBUY73AA6CTTYL3LRWHNFDULV7PFPN/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/52N5XS73Z5S4ZN7I7R56ICCPCTKCUV4H/
- https://www.exploit-db.com/download/47655Exploit, Third Party Advisory, VDB Entry
- https://github.com/yaml/pyyaml/blob/master/CHANGESRelease Notes, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/33VBUY73AA6CTTYL3LRWHNFDULV7PFPN/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/52N5XS73Z5S4ZN7I7R56ICCPCTKCUV4H/
- https://www.exploit-db.com/download/47655Exploit, Third Party Advisory, VDB Entry
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.