{"id":"CVE-2021-4001","revision":"3d76408107e04242b47bce8c8db50b6f","records":[{"revision":"3d76408107e04242b47bce8c8db50b6f","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2021-4001","aliases":[],"title":"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 …","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":0,"publishedAt":"2022-01-21T00:00:00+00:00","modifiedAt":"2026-10-08T21:03:26.368+00:00","affected":[{"ecosystem":"Vendor product","name":"kernel","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"n/a\",\n                    \"product\": \"kernel\",\n                    \"versions\": [\n                        {\n                            \"version\": \"kernel 5.16 rc2\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://bugzilla.redhat.com/show_bug.cgi?id=2025645","https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=353050be4c19e102178ccc05988101887c25ae53"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2021-4001","license":"CVE Program Terms of Use","key":"cve-program:CVE-2021-4001","identifiers":["CVE-2021-4001"]},"retained":false,"historicalAffected":[]}],"coverage":[]}