{"id":"CVE-2017-18342","url":"https://www.cyber-defence.io/tools/cve/CVE-2017-18342","generatedAt":"2026-10-28T20:48:03.932Z","title":"In PyYAML before 5.1, the yaml.load() API could execute arbitrary code if used with untrusted data.","description":"In PyYAML before 5.1, the yaml.load() API could execute arbitrary code if used with untrusted data. The load() function has been deprecated in version 5.1 and the 'UnsafeLoader' has been introduced for backward compatibility with the function.","published":"2018-06-27T12:29:00.000Z","lastModified":"2026-06-17T01:12:39.000Z","status":"Modified","sourceIdentifier":"cve@mitre.org","cvss":{"version":"3.1","score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-502"],"affected":["pyyaml/pyyaml","fedoraproject/fedora"],"epss":{"score":0.05656,"percentile":0.9293,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (5.66%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://github.com/marshmallow-code/apispec/issues/278","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/yaml/pyyaml/blob/master/CHANGES","tags":["Release Notes","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/yaml/pyyaml/issues/193","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/yaml/pyyaml/pull/74","tags":["Patch","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/yaml/pyyaml/wiki/PyYAML-yaml.load%28input%29-Deprecation","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JEX7IPV5P2QJITAMA5Z63GQCZA5I6NVZ/","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KSQQMRUQSXBSUXLCRD3TSZYQ7SEZRKCE/","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/M6JCFGEIEOFMWWIXGHSELMKQDD4CV2BA/","source":"cve@mitre.org"},{"url":"https://security.gentoo.org/glsa/202003-45","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/marshmallow-code/apispec/issues/278","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/yaml/pyyaml/blob/master/CHANGES","tags":["Release Notes","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/yaml/pyyaml/issues/193","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/yaml/pyyaml/pull/74","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/yaml/pyyaml/wiki/PyYAML-yaml.load%28input%29-Deprecation","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JEX7IPV5P2QJITAMA5Z63GQCZA5I6NVZ/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KSQQMRUQSXBSUXLCRD3TSZYQ7SEZRKCE/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/M6JCFGEIEOFMWWIXGHSELMKQDD4CV2BA/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.gentoo.org/glsa/202003-45","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2017-18342","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}