{"id":"CVE-2018-1061","url":"https://www.cyber-defence.io/tools/cve/CVE-2018-1061","generatedAt":"2026-10-28T22:13:42.276Z","title":"python before versions 2.7.15, 3.4.9, 3.5.6rc1, 3.6.5rc1 and 3.7.0 is vulnerable to catastrophic backtracking in the difflib.IS_LINE_JUNK method.","description":"python before versions 2.7.15, 3.4.9, 3.5.6rc1, 3.6.5rc1 and 3.7.0 is vulnerable to catastrophic backtracking in the difflib.IS_LINE_JUNK method.  An attacker could use this flaw to cause denial of service.","published":"2018-06-19T12:29:00.000Z","lastModified":"2026-10-15T18:17:18.000Z","status":"Modified","sourceIdentifier":"secalert@redhat.com","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-20"],"affected":["python/python","debian/debian linux","redhat/ansible tower","redhat/enterprise linux desktop","redhat/enterprise linux server","redhat/enterprise linux workstation","canonical/ubuntu linux","fedoraproject/fedora"],"epss":{"score":0.04742,"percentile":0.91819,"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 (4.74%). 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":"secalert@redhat.com"},{"url":"http://www.securitytracker.com/id/1042001","tags":["Third Party Advisory","VDB Entry"],"source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHBA-2019:0327","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2018:3041","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2018:3505","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2019:1260","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2019:3725","source":"secalert@redhat.com"},{"url":"https://bugs.python.org/issue32981","tags":["Vendor Advisory"],"source":"secalert@redhat.com"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-1061","tags":["Issue Tracking"],"source":"secalert@redhat.com"},{"url":"https://docs.python.org/3.5/whatsnew/changelog.html#python-3-5-6-release-candidate-1","tags":["Vendor Advisory"],"source":"secalert@redhat.com"},{"url":"https://docs.python.org/3.6/whatsnew/changelog.html#python-3-6-5-release-candidate-1","tags":["Vendor Advisory"],"source":"secalert@redhat.com"},{"url":"https://lists.debian.org/debian-lts-announce/2018/09/msg00030.html","tags":["Mailing List","Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://lists.debian.org/debian-lts-announce/2018/09/msg00031.html","tags":["Mailing List","Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/46PVWY5LFP4BRPG3BVQ5QEEFYBVEXHCK/","source":"secalert@redhat.com"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AEZ5IQT7OF7Q2NCGIVABOWYGKO7YU3NJ/","source":"secalert@redhat.com"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JSKPGPZQNTAULHW4UH63KGOOUIDE4RRB/","source":"secalert@redhat.com"},{"url":"https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbst03951en_us","source":"secalert@redhat.com"},{"url":"https://usn.ubuntu.com/3817-1/","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://usn.ubuntu.com/3817-2/","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://www.debian.org/security/2018/dsa-4306","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://www.debian.org/security/2018/dsa-4307","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00040.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.securitytracker.com/id/1042001","tags":["Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHBA-2019:0327","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2018:3041","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2018:3505","tags":["Third Party 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Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.debian.org/security/2018/dsa-4306","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.debian.org/security/2018/dsa-4307","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2018-1061","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."}