{"id":"CVE-2018-20784","url":"https://www.cyber-defence.io/tools/cve/CVE-2018-20784","generatedAt":"2026-10-29T01:51:14.301Z","title":"In the Linux kernel before 4.20.2, kernel/sched/fair.c mishandles leaf cfs_rq's, which allows attackers to cause a denial of service (infinite loop in update_blocked_averages) or possibly have unspecified other impact by inducing a high load.","description":"In the Linux kernel before 4.20.2, kernel/sched/fair.c mishandles leaf cfs_rq's, which allows attackers to cause a denial of service (infinite loop in update_blocked_averages) or possibly have unspecified other impact by inducing a high load.","published":"2019-02-22T15:29:00.000Z","lastModified":"2026-06-17T01:53:28.000Z","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-835"],"affected":["linux/linux kernel","canonical/ubuntu linux","redhat/enterprise linux","redhat/enterprise linux for real time"],"epss":{"score":0.04173,"percentile":0.90851,"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 (4.17%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=c40f7d74c741a907cfaeb73a7697081881c497d0","tags":["Patch","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHSA-2019:1959","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHSA-2019:1971","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.20.2","tags":["Release Notes","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/torvalds/linux/commit/c40f7d74c741a907cfaeb73a7697081881c497d0","tags":["Patch","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://usn.ubuntu.com/4115-1/","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://usn.ubuntu.com/4118-1/","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://usn.ubuntu.com/4211-1/","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://usn.ubuntu.com/4211-2/","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=c40f7d74c741a907cfaeb73a7697081881c497d0","tags":["Patch","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2019:1959","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2019:1971","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.20.2","tags":["Release Notes","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/torvalds/linux/commit/c40f7d74c741a907cfaeb73a7697081881c497d0","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://usn.ubuntu.com/4115-1/","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://usn.ubuntu.com/4118-1/","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://usn.ubuntu.com/4211-1/","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://usn.ubuntu.com/4211-2/","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2018-20784","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."}