CVE-2021-4001

Severity Score

4.1

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

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.

Se ha encontrado una condición de carrera en el verificador ebpf del kernel de Linux entre las funciones bpf_map_update_elem y bpf_map_freeze debido a la falta de un bloqueo en el archivo kernel/bpf/syscall.c. En este fallo, un usuario local con un privilegio especial (cap_sys_admin o cap_bpf) puede modificar el espacio de direcciones mapeado congelado. Este fallo afecta a las versiones del kernel anteriores a 5.16 rc2

*Credits: N/A

Attack Vector

Local

Attack Complexity

High

Privileges Required

High

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

High

Availability

None

Attack Vector

Local

Attack Complexity

Medium

Authentication

None

Confidentiality

None

Integrity

Complete

Availability

None

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2021-11-22 CVE Reserved
2022-01-06 CVE Published
2023-03-08 EPSS Updated
2024-08-03 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition

CAPEC

References (2)

URL	Tag	Source

URL	Date	SRC

URL	Date	SRC
https://bugzilla.redhat.com/show_bug.cgi?id=2025645	2022-11-16
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=353050be4c19e102178ccc05988101887c25ae53	2022-11-16

URL	Date	SRC

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				<= 5.15 Search vendor "Linux" for product "Linux Kernel" and version " <= 5.15"		-		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				5.16 Search vendor "Linux" for product "Linux Kernel" and version "5.16"		rc1		Affected