CVE-2021-4001
medium
CVSS v3
—
CVSS v2
—
VIR risk
5.5
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.
Predictions
Exploit likelihood
20%
Patch ETA
—
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2021-4001
Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2021-4001.html
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| arch | fixed | 5.10.83-1 | |
| sles | affected | | |
| debian | bookworm | fixed | 5.15.5-1 |
| debian | bullseye | fixed | 5.10.84-1 |
| debian | forky | fixed | 5.15.5-1 |
| debian | sid | fixed | 5.15.5-1 |
| debian | trixie | fixed | 5.15.5-1 |
References
Verify integrity in audit chain (admin only). AS-IS.