vulnerability

Debian: CVE-2021-4001: linux -- security update

Severity
5
CVSS
(AV:L/AC:M/Au:N/C:N/I:C/A:N)
Published
Jan 21, 2022
Added
Jul 30, 2024
Modified
Mar 30, 2026

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

debian-upgrade-linux
Title
Rapid7 Labs

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