vulnerability
Red Hat: CVE-2021-4001: kernel: race condition when the EBPF map is frozen
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 5 | (AV:L/AC:M/Au:N/C:N/I:C/A:N) | Jan 21, 2022 | Jul 9, 2025 | Jul 9, 2025 |
Severity
5
CVSS
(AV:L/AC:M/Au:N/C:N/I:C/A:N)
Published
Jan 21, 2022
Added
Jul 9, 2025
Modified
Jul 9, 2025
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.
Solution
no-fix-redhat-rpm-package
References
Rapid7 Labs
2026 Global Threat Landscape Report
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