{"api_version":"1","generated_at":"2026-04-23T07:00:50+00:00","cve":"CVE-2021-20286","urls":{"html":"https://cve.report/CVE-2021-20286","api":"https://cve.report/api/cve/CVE-2021-20286.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2021-20286","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-20286"},"summary":{"title":"CVE-2021-20286","description":"A flaw was found in libnbd 1.7.3. An assertion failure in nbd_unlocked_opt_go in ilb/opt.c may lead to denial of service.","state":"PUBLIC","assigner":"secalert@redhat.com","published_at":"2021-03-15 18:15:00","updated_at":"2021-03-22 14:32:00"},"problem_types":["CWE-617"],"metrics":[],"references":[{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=1934727","name":"https://bugzilla.redhat.com/show_bug.cgi?id=1934727","refsource":"MISC","tags":["Issue Tracking","Third Party Advisory"],"title":"1934727 – (CVE-2021-20286) CVE-2021-20286 libnbd: Assertion failure in nbd_unlocked_opt_go in lib/opt.c","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://gitlab.com/nbdkit/libnbd/-/commit/fb4440de9cc76e9c14bd3ddf3333e78621f40ad0","name":"https://gitlab.com/nbdkit/libnbd/-/commit/fb4440de9cc76e9c14bd3ddf3333e78621f40ad0","refsource":"MISC","tags":["Patch","Third Party Advisory"],"title":"opt_go: Tolerate unplanned server death (fb4440de) · Commits · nbdkit / libnbd · GitLab","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-20286","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-20286","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[{"cve_year":"2021","cve_id":"20286","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"o","cpe4":"redhat","cpe5":"enterprise_linux","cpe6":"8.3.0","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"advanced_virtualization","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"20286","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"a","cpe4":"redhat","cpe5":"libnbd","cpe6":"*","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"}],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[{"cve":"CVE-2021-20286","qid":"183532","title":"Debian Security Update for libnbd (CVE-2021-20286)"},{"cve":"CVE-2021-20286","qid":"750785","title":"OpenSUSE Security Update for kubevirt (openSUSE-SU-2021:2274-1)"},{"cve":"CVE-2021-20286","qid":"901415","title":"Common Base Linux Mariner (CBL-Mariner) Security Update for libnbd (7265-1)"}]},"source_records":{"cve_program":{"data_type":"CVE","data_format":"MITRE","data_version":"4.0","CVE_data_meta":{"ID":"CVE-2021-20286","ASSIGNER":"secalert@redhat.com","STATE":"PUBLIC"},"affects":{"vendor":{"vendor_data":[{"vendor_name":"n/a","product":{"product_data":[{"product_name":"libnbd","version":{"version_data":[{"version_value":"libnbd 1.7.3"}]}}]}}]}},"problemtype":{"problemtype_data":[{"description":[{"lang":"eng","value":"CWE-617"}]}]},"references":{"reference_data":[{"refsource":"MISC","name":"https://bugzilla.redhat.com/show_bug.cgi?id=1934727","url":"https://bugzilla.redhat.com/show_bug.cgi?id=1934727"},{"refsource":"MISC","name":"https://gitlab.com/nbdkit/libnbd/-/commit/fb4440de9cc76e9c14bd3ddf3333e78621f40ad0","url":"https://gitlab.com/nbdkit/libnbd/-/commit/fb4440de9cc76e9c14bd3ddf3333e78621f40ad0"}]},"description":{"description_data":[{"lang":"eng","value":"A flaw was found in libnbd 1.7.3. An assertion failure in nbd_unlocked_opt_go in ilb/opt.c may lead to denial of service."}]}},"nvd":{"publishedDate":"2021-03-15 18:15:00","lastModifiedDate":"2021-03-22 14:32:00","problem_types":["CWE-617"],"metrics":{"baseMetricV3":{"cvssV3":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:L","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"HIGH","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"LOW","baseScore":2.7,"baseSeverity":"LOW"},"exploitabilityScore":1.2,"impactScore":1.4},"baseMetricV2":{"cvssV2":{"version":"2.0","vectorString":"AV:N/AC:L/Au:S/C:N/I:N/A:P","accessVector":"NETWORK","accessComplexity":"LOW","authentication":"SINGLE","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"PARTIAL","baseScore":4},"severity":"MEDIUM","exploitabilityScore":8,"impactScore":2.9,"acInsufInfo":false,"obtainAllPrivilege":false,"obtainUserPrivilege":false,"obtainOtherPrivilege":false,"userInteractionRequired":false}},"configurations":{"CVE_data_version":"4.0","nodes":[{"operator":"OR","children":[],"cpe_match":[{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:redhat:libnbd:*:*:*:*:*:*:*:*","versionEndExcluding":"1.7.3","cpe_name":[]},{"vulnerable":true,"cpe23Uri":"cpe:2.3:o:redhat:enterprise_linux:8.3.0:*:*:*:advanced_virtualization:*:*:*","cpe_name":[]}]}]}},"legacy_mitre":{"record":{"CveYear":"2021","CveId":"20286","Ordinal":"194327","Title":"CVE-2021-20286","CVE":"CVE-2021-20286","Year":"2021"},"notes":[{"CveYear":"2021","CveId":"20286","Ordinal":"1","NoteData":"A flaw was found in libnbd 1.7.3. An assertion failure in nbd_unlocked_opt_go in ilb/opt.c may lead to denial of service.","Type":"Description","Title":null},{"CveYear":"2021","CveId":"20286","Ordinal":"2","NoteData":"2021-03-15","Type":"Other","Title":"Published"},{"CveYear":"2021","CveId":"20286","Ordinal":"3","NoteData":"2021-03-15","Type":"Other","Title":"Modified"}]}}}