CVE-2021-4001 — Time-of-check Time-of-use (TOCTOU) Race Condition in Linux
Severity
4.1MEDIUMNVD
OSV4.7
EPSS
0.0%
top 96.35%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
Timeline
PublishedJan 21
Latest updateOct 4
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:NExploitability: 0.5 | Impact: 3.6
Affected Packages6 packages
Patches
🔴Vulnerability Details
6OSV▶
linux, linux-aws, linux-aws-5.4, linux-azure, linux-azure-5.4, linux-bluefield, linux-gcp, linux-gcp-5.4, linux-gkeop, linux-hwe-5.4, linux-ibm, linux-ibm-5.4, linux-iot, linux-kvm, linux-oracle, linu↗2023-10-04
OSV▶
linux, linux-aws, linux-aws-5.11, linux-aws-5.13, linux-azure-5.11, linux-gcp, linux-gcp-5.11, linux-hwe-5.13, linux-kvm, linux-oem-5.13, linux-oracle, linux-oracle-5.11, linux-raspi vulnerabilities↗2022-02-03
GHSA▶
GHSA-q6qm-pxcx-gj5h: 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/sysc↗2022-01-22
OSV▶
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/sysc↗2022-01-21
📋Vendor Advisories
7Microsoft▶
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 pr↗2022-01-11