{"id":"CVE-2018-20406","url":"https://www.cyber-defence.io/tools/cve/CVE-2018-20406","generatedAt":"2026-10-28T21:22:16.279Z","title":"Modules/_pickle.c in Python before 3.7.1 has an integer overflow via a large LONG_BINPUT value that is mishandled during a \"resize to twice the size\" attempt.","description":"Modules/_pickle.c in Python before 3.7.1 has an integer overflow via a large LONG_BINPUT value that is mishandled during a \"resize to twice the size\" attempt. This issue might cause memory exhaustion, but is only relevant if the pickle format is used for serializing tens or hundreds of gigabytes of data. This issue is fixed in: v3.4.10, v3.4.10rc1; v3.5.10, v3.5.10rc1, v3.5.7, v3.5.7rc1, v3.5.8, v3.5.8rc1, v3.5.8rc2, v3.5.9; v3.6.10, v3.6.10rc1, v3.6.11, v3.6.11rc1, v3.6.12, v3.6.7, v3.6.7rc1, v3.6.7rc2, v3.6.8, v3.6.8rc1, v3.6.9, v3.6.9rc1; v3.7.1, v3.7.1rc1, v3.7.1rc2, v3.7.2, v3.7.2rc1, v3.7.3, v3.7.3rc1, v3.7.4, v3.7.4rc1, v3.7.4rc2, v3.7.5, v3.7.5rc1, v3.7.6, v3.7.6rc1, v3.7.7, v3.7.7rc1, v3.7.8, v3.7.8rc1, v3.7.9.","published":"2018-12-23T23:29:00.000Z","lastModified":"2026-10-15T18:17:20.000Z","status":"Modified","sourceIdentifier":"cve@mitre.org","cvss":{"version":"3.0","score":7.5,"severity":"HIGH","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-190"],"affected":["python/python","debian/debian linux","fedoraproject/fedora"],"epss":{"score":0.05789,"percentile":0.93064,"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 (5.79%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00040.html","source":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHSA-2019:3725","source":"cve@mitre.org"},{"url":"https://bugs.python.org/issue34656","tags":["Exploit","Issue Tracking","Patch","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/python/cpython/commit/a4ae828ee416a66d8c7bf5ee71d653c2cc6a26dd","tags":["Patch","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.debian.org/debian-lts-announce/2019/02/msg00011.html","tags":["Mailing List","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.debian.org/debian-lts-announce/2020/07/msg00011.html","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/46PVWY5LFP4BRPG3BVQ5QEEFYBVEXHCK/","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AEZ5IQT7OF7Q2NCGIVABOWYGKO7YU3NJ/","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/D3LXPABKVLFYUHRYJPM3CSS5MS6FXKS7/","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ICBEGRHIPHWPG2VGYS6R4EVKVUUF4AQW/","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JSKPGPZQNTAULHW4UH63KGOOUIDE4RRB/","source":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TR6GCO3WTV4D5L23WTCBF275VE6BVNI3/","source":"cve@mitre.org"},{"url":"https://security.netapp.com/advisory/ntap-20190416-0010/","source":"cve@mitre.org"},{"url":"https://usn.ubuntu.com/4127-1/","source":"cve@mitre.org"},{"url":"https://usn.ubuntu.com/4127-2/","source":"cve@mitre.org"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00040.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2019:3725","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://bugs.python.org/issue34656","tags":["Exploit","Issue Tracking","Patch","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/python/cpython/commit/a4ae828ee416a66d8c7bf5ee71d653c2cc6a26dd","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2019/02/msg00011.html","tags":["Mailing List","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2020/07/msg00011.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/46PVWY5LFP4BRPG3BVQ5QEEFYBVEXHCK/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AEZ5IQT7OF7Q2NCGIVABOWYGKO7YU3NJ/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/D3LXPABKVLFYUHRYJPM3CSS5MS6FXKS7/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ICBEGRHIPHWPG2VGYS6R4EVKVUUF4AQW/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JSKPGPZQNTAULHW4UH63KGOOUIDE4RRB/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TR6GCO3WTV4D5L23WTCBF275VE6BVNI3/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.netapp.com/advisory/ntap-20190416-0010/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://usn.ubuntu.com/4127-1/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://usn.ubuntu.com/4127-2/","source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2018-20406","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."}