cbcvebase.
CVE-2021-4001
published 2022-01-21

CVE-2021-4001: 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…

PriorityP415medium4.1CVSS 3.1
AVLACHPRHUINSUCNIHAN
EPSS
0.19%
8.5th percentile
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.

Affected

10 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.15.5-1 (bookworm)linux 5.15.5-1 (bookworm)
linuxlinux_kernel<= 5.15
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.84-15.10.84-1
linuxlinux_kernel>= 0 < 5.15.5-15.15.5-1
linuxlinux_kernel>= 0 < 5.15.5-15.15.5-1
linuxlinux_kernel>= 0 < 5.15.5-15.15.5-1
linuxlinux_kernel>= 0 < 5.4.0-164.1815.4.0-164.181
msrccm1_kernel_5.10.93.1-4_on_cbl_mariner_1.0

CVSS provenance

nvdv3.14.1MEDIUMCVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:H/A:N
nvdv2.04.7MEDIUMAV:L/AC:M/Au:N/C:N/I:C/A:N
osv4.7MEDIUM
vendor_ubuntu4.7MEDIUM
vendor_debian4.1MEDIUM
vendor_msrc4.1MEDIUM
vendor_redhat4.1MEDIUM
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