Vulnerability 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.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux Kernel | <= 5.15 |
Related Weaknesses (CWE)
References
- https://bugzilla.redhat.com/show_bug.cgi?id=2025645Issue TrackingPatchThird Party Advisory
- https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=353050be4PatchThird Party Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2025645Issue TrackingPatchThird Party Advisory
- https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=353050be4PatchThird Party Advisory
FAQ
What is CVE-2021-4001?
CVE-2021-4001 is a vulnerability with a CVSS score of 4.1 (MEDIUM). 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 p...
How severe is CVE-2021-4001?
CVE-2021-4001 has been rated MEDIUM with a CVSS base score of 4.1/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2021-4001?
Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel.