{"id":"CVE-2018-20856","url":"https://www.cyber-defence.io/tools/cve/CVE-2018-20856","generatedAt":"2026-10-28T20:12:34.250Z","title":"In block/blk-core.c, there is an __blk_drain_queue() use-after-free because a certain error case is mishandled.","description":"An issue was discovered in the Linux kernel before 4.18.7. In block/blk-core.c, there is an __blk_drain_queue() use-after-free because a certain error case is mishandled.","published":"2019-07-26T05:15:11.000Z","lastModified":"2026-06-17T01:53:36.000Z","status":"Modified","sourceIdentifier":"cve@mitre.org","cvss":{"version":"3.0","score":7.8,"severity":"HIGH","vector":"CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-416"],"affected":["linux/linux kernel"],"epss":{"score":0.00707,"percentile":0.53219,"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 (0.71%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"http://packetstormsecurity.com/files/154059/Slackware-Security-Advisory-Slackware-14.2-kernel-Updates.html","source":"cve@mitre.org"},{"url":"http://packetstormsecurity.com/files/154408/Kernel-Live-Patch-Security-Notice-LSN-0055-1.html","source":"cve@mitre.org"},{"url":"http://packetstormsecurity.com/files/154951/Kernel-Live-Patch-Security-Notice-LSN-0058-1.html","source":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHSA-2019:3055","source":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHSA-2019:3076","source":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHSA-2019:3089","source":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHSA-2019:3217","source":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHSA-2020:0100","source":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHSA-2020:0103","source":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHSA-2020:0543","source":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHSA-2020:0664","source":"cve@mitre.org"},{"url":"https://access.redhat.com/errata/RHSA-2020:0698","source":"cve@mitre.org"},{"url":"https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.18.7","tags":["Mailing List","Release Notes","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=54648cf1ec2d7f4b6a71767799c45676a138ca24","tags":["Mailing List","Patch","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/torvalds/linux/commit/54648cf1ec2d7f4b6a71767799c45676a138ca24","tags":["Patch","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.debian.org/debian-lts-announce/2019/08/msg00017.html","source":"cve@mitre.org"},{"url":"https://seclists.org/bugtraq/2019/Aug/18","source":"cve@mitre.org"},{"url":"https://seclists.org/bugtraq/2019/Aug/26","source":"cve@mitre.org"},{"url":"https://security.netapp.com/advisory/ntap-20190905-0002/","source":"cve@mitre.org"},{"url":"https://support.f5.com/csp/article/K14673240?utm_source=f5support&amp%3Butm_medium=RSS","source":"cve@mitre.org"},{"url":"https://usn.ubuntu.com/4094-1/","source":"cve@mitre.org"},{"url":"https://usn.ubuntu.com/4116-1/","source":"cve@mitre.org"},{"url":"https://usn.ubuntu.com/4118-1/","source":"cve@mitre.org"},{"url":"https://www.debian.org/security/2019/dsa-4497","source":"cve@mitre.org"},{"url":"http://packetstormsecurity.com/files/154059/Slackware-Security-Advisory-Slackware-14.2-kernel-Updates.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://packetstormsecurity.com/files/154408/Kernel-Live-Patch-Security-Notice-LSN-0055-1.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://packetstormsecurity.com/files/154951/Kernel-Live-Patch-Security-Notice-LSN-0058-1.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2019:3055","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2019:3076","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2019:3089","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2019:3217","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2020:0100","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2020:0103","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2020:0543","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2020:0664","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2020:0698","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.18.7","tags":["Mailing List","Release Notes","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=54648cf1ec2d7f4b6a71767799c45676a138ca24","tags":["Mailing List","Patch","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/torvalds/linux/commit/54648cf1ec2d7f4b6a71767799c45676a138ca24","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2019/08/msg00017.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://seclists.org/bugtraq/2019/Aug/18","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://seclists.org/bugtraq/2019/Aug/26","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.netapp.com/advisory/ntap-20190905-0002/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://support.f5.com/csp/article/K14673240?utm_source=f5support&amp%3Butm_medium=RSS","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://usn.ubuntu.com/4094-1/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://usn.ubuntu.com/4116-1/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://usn.ubuntu.com/4118-1/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.debian.org/security/2019/dsa-4497","source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2018-20856","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."}