CVE-2021-4001 Information

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 Vector

CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:H/A:N

Reference

https://bugzilla.redhat.com/show_bug.cgi?id=2025645 https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=353050be4c19e102178ccc05988101887c25ae53

Attack Complexity

HIGH

Privileges Required

HIGH

User Interaction Required

HIGH

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

NONE

Availability Impact

HIGH

Base Score

NONE

Base Severity

4.1