{"api_version":"1","generated_at":"2026-04-22T21:27:18+00:00","cve":"CVE-2021-4001","urls":{"html":"https://cve.report/CVE-2021-4001","api":"https://cve.report/api/cve/CVE-2021-4001.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2021-4001","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-4001"},"summary":{"title":"CVE-2021-4001","description":"A race condition was found in the Linux kernel's ebpf verifier between bpf_map_update_elem and bpf_map_freeze due to a missing lock in kernel/bpf/syscall.c. In this flaw, a local user with a special privilege (cap_sys_admin or cap_bpf) can modify the frozen mapped address space. This flaw affects kernel versions prior to 5.16 rc2.","state":"PUBLIC","assigner":"secalert@redhat.com","published_at":"2022-01-21 19:15:00","updated_at":"2022-11-16 03:36:00"},"problem_types":["CWE-367"],"metrics":[],"references":[{"url":"https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=353050be4c19e102178ccc05988101887c25ae53","name":"https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=353050be4c19e102178ccc05988101887c25ae53","refsource":"MISC","tags":[],"title":"kernel/git/bpf/bpf.git - BPF kernel tree","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2025645","name":"https://bugzilla.redhat.com/show_bug.cgi?id=2025645","refsource":"MISC","tags":[],"title":"2025645 – (CVE-2021-4001) CVE-2021-4001 kernel: race condition when the EBPF map is frozen","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-4001","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-4001","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[{"cve_year":"2021","cve_id":"4001","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"o","cpe4":"linux","cpe5":"linux_kernel","cpe6":"5.16","cpe7":"rc1","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"4001","vulnerable":"1","versionEndIncluding":"5.15","cpe1":"cpe","cpe2":"2.3","cpe3":"o","cpe4":"linux","cpe5":"linux_kernel","cpe6":"*","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"}],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[{"cve":"CVE-2021-4001","qid":"180355","title":"Debian Security Update for linux (CVE-2021-4001)"},{"cve":"CVE-2021-4001","qid":"198616","title":"Ubuntu Security Notification for Linux kernel (OEM) Vulnerabilities (USN-5207-1)"},{"cve":"CVE-2021-4001","qid":"198653","title":"Ubuntu Security Notification for Linux kernel Vulnerabilities (USN-5265-1)"},{"cve":"CVE-2021-4001","qid":"198659","title":"Ubuntu Security Notification for Linux kernel (OEM) Vulnerabilities (USN-5278-1)"},{"cve":"CVE-2021-4001","qid":"199804","title":"Ubuntu Security Notification for Linux kernel Vulnerabilities (USN-6417-1)"},{"cve":"CVE-2021-4001","qid":"282087","title":"Fedora Security Update for kernel (FEDORA-2021-c0dc424b7d)"},{"cve":"CVE-2021-4001","qid":"282133","title":"Fedora Security Update for kernel (FEDORA-2021-19ad835cb3)"},{"cve":"CVE-2021-4001","qid":"353141","title":"Amazon Linux Security Advisory for kernel : ALAS2KERNEL-5.4-2022-010"},{"cve":"CVE-2021-4001","qid":"353152","title":"Amazon Linux Security Advisory for kernel : ALAS2KERNEL-5.10-2022-008"},{"cve":"CVE-2021-4001","qid":"751590","title":"OpenSUSE Security Update for the Linux Kernel (openSUSE-SU-2022:0056-1)"},{"cve":"CVE-2021-4001","qid":"751622","title":"OpenSUSE Security Update for the Linux Kernel (openSUSE-SU-2022:0131-1)"},{"cve":"CVE-2021-4001","qid":"751654","title":"SUSE Enterprise Linux Security Update for the Linux Kernel (SUSE-SU-2022:0197-1)"},{"cve":"CVE-2021-4001","qid":"751989","title":"SUSE Enterprise Linux Security Update for the Linux Kernel (SUSE-SU-2022:0131-1)"},{"cve":"CVE-2021-4001","qid":"753132","title":"SUSE Enterprise Linux Security Update for the Linux Kernel (Live Patch 2 for SLE 15 SP3) (SUSE-SU-2022:0978-1)"},{"cve":"CVE-2021-4001","qid":"753133","title":"SUSE Enterprise Linux Security Update for the Linux Kernel (SUSE-SU-2022:0181-1)"},{"cve":"CVE-2021-4001","qid":"753264","title":"SUSE Enterprise Linux Security Update for the Linux Kernel (SUSE-SU-2022:0079-1)"},{"cve":"CVE-2021-4001","qid":"753355","title":"SUSE Enterprise Linux Security Update for the Linux Kernel (SUSE-SU-2022:0056-1)"},{"cve":"CVE-2021-4001","qid":"753487","title":"SUSE Enterprise Linux Security Update for the Linux Kernel (Live Patch 10 for SLE 15 SP3) (SUSE-SU-2022:0984-1)"},{"cve":"CVE-2021-4001","qid":"900617","title":"Common Base Linux Mariner (CBL-Mariner) Security Update for kernel (8322)"},{"cve":"CVE-2021-4001","qid":"905851","title":"Common Base Linux Mariner (CBL-Mariner) Security Update for kernel (8322-1)"}]},"source_records":{"cve_program":{"data_type":"CVE","data_format":"MITRE","data_version":"4.0","CVE_data_meta":{"ID":"CVE-2021-4001","ASSIGNER":"secalert@redhat.com","STATE":"PUBLIC"},"affects":{"vendor":{"vendor_data":[{"vendor_name":"n/a","product":{"product_data":[{"product_name":"kernel","version":{"version_data":[{"version_value":"kernel 5.16 rc2"}]}}]}}]}},"problemtype":{"problemtype_data":[{"description":[{"lang":"eng","value":"CWE-367"}]}]},"references":{"reference_data":[{"refsource":"MISC","name":"https://bugzilla.redhat.com/show_bug.cgi?id=2025645","url":"https://bugzilla.redhat.com/show_bug.cgi?id=2025645"},{"refsource":"MISC","name":"https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=353050be4c19e102178ccc05988101887c25ae53","url":"https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=353050be4c19e102178ccc05988101887c25ae53"}]},"description":{"description_data":[{"lang":"eng","value":"A race condition was found in the Linux kernel's ebpf verifier between bpf_map_update_elem and bpf_map_freeze due to a missing lock in kernel/bpf/syscall.c. In this flaw, a local user with a special privilege (cap_sys_admin or cap_bpf) can modify the frozen mapped address space. This flaw affects kernel versions prior to 5.16 rc2."}]}},"nvd":{"publishedDate":"2022-01-21 19:15:00","lastModifiedDate":"2022-11-16 03:36:00","problem_types":["CWE-367"],"metrics":{"baseMetricV3":{"cvssV3":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:H/A:N","attackVector":"LOCAL","attackComplexity":"HIGH","privilegesRequired":"HIGH","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"HIGH","availabilityImpact":"NONE","baseScore":4.1,"baseSeverity":"MEDIUM"},"exploitabilityScore":0.5,"impactScore":3.6},"baseMetricV2":{"cvssV2":{"version":"2.0","vectorString":"AV:L/AC:M/Au:N/C:N/I:C/A:N","accessVector":"LOCAL","accessComplexity":"MEDIUM","authentication":"NONE","confidentialityImpact":"NONE","integrityImpact":"COMPLETE","availabilityImpact":"NONE","baseScore":4.7},"severity":"MEDIUM","exploitabilityScore":3.4,"impactScore":6.9,"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:o:linux:linux_kernel:5.16:rc1:*:*:*:*:*:*","cpe_name":[]},{"vulnerable":true,"cpe23Uri":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndIncluding":"5.15","cpe_name":[]}]}]}},"legacy_mitre":{"record":{"CveYear":"2021","CveId":"4001","Ordinal":"221795","Title":"CVE-2021-4001","CVE":"CVE-2021-4001","Year":"2021"},"notes":[{"CveYear":"2021","CveId":"4001","Ordinal":"1","NoteData":"A race condition was found in the Linux kernel's ebpf verifier between bpf_map_update_elem and bpf_map_freeze due to a missing lock in kernel/bpf/syscall.c. In this flaw, a local user with a special privilege (cap_sys_admin or cap_bpf) can modify the frozen mapped address space. This flaw affects kernel versions prior to 5.16 rc2.","Type":"Description","Title":null},{"CveYear":"2021","CveId":"4001","Ordinal":"2","NoteData":"2022-01-21","Type":"Other","Title":"Published"},{"CveYear":"2021","CveId":"4001","Ordinal":"3","NoteData":"2022-01-21","Type":"Other","Title":"Modified"}]}}}