{"id":"UBUNTU-CVE-2019-20477","details":"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of an incomplete fix for CVE-2017-18342.","modified":"2025-07-16T07:39:57.034932Z","published":"2020-02-19T04:15:00Z","withdrawn":"2025-07-18T16:45:35Z","upstream":["CVE-2019-20477"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2019-20477"},{"type":"REPORT","url":"https://github.com/yaml/pyyaml/blob/master/CHANGES"},{"type":"REPORT","url":"https://www.exploit-db.com/download/47655"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2019-20477"}],"affected":[{"package":{"name":"pyyaml","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/pyyaml@5.3-1ubuntu2?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.3-1ubuntu2"}]}],"versions":["5.1.2-1","5.1.2-1build1","5.3-1ubuntu1"],"ecosystem_specific":{"binaries":[{"binary_version":"5.3-1ubuntu2","binary_name":"python-yaml"},{"binary_version":"5.3-1ubuntu2","binary_name":"python-yaml-dbg"},{"binary_version":"5.3-1ubuntu2","binary_name":"python3-yaml"},{"binary_version":"5.3-1ubuntu2","binary_name":"python3-yaml-dbg"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2019/UBUNTU-CVE-2019-20477.json"}}],"schema_version":"1.7.3","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"low"}]}