Is CVE-2021-4001 in the CISA KEV catalog?

No. CVE-2021-4001 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2021-4001?

CVE-2021-4001 has a CVSS v3 base score of 4.1 (MEDIUM).

What is the EPSS score for CVE-2021-4001?

CVE-2021-4001 has an EPSS score of 0.19% (8th percentile), estimating the probability of exploitation in the next 30 days.

How do I fix CVE-2021-4001?

Upgrade linux on debian 11 to 5.10.84-1 or later. Fixes are available for 90 affected products.

CVE & CISA-KEV Catalog

CVE-2021-4001

MEDIUM

4.1

CVSS v3

NVD

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.

CWE-367TOCTOU Race Condition

How to fix

Remediation Available

linuxDebian

Fixed in:5.10.84-1CVE-2021-4001

Fixed in:5.15.5-1CVE-2021-4001

linuxUbuntu

Fixed in:5.4.0-164.181USN-6417-1

linux-awsUbuntu

Fixed in:5.4.0-1111.120USN-6417-1

linux-aws-5.11Ubuntu

Fixed in:5.11.0-1028.31~20.04.1USN-5265-1

linux-aws-5.13Ubuntu

Fixed in:5.13.0-1012.13~20.04.1USN-5265-1

linux-aws-5.4Ubuntu

Fixed in:5.4.0-1111.120~18.04.1USN-6417-1

linux-azureUbuntu

Fixed in:5.4.0-1117.124USN-6417-1

linux-azure-5.11Ubuntu

Fixed in:5.11.0-1028.31~20.04.2USN-5265-1

linux-azure-5.4Ubuntu

Fixed in:5.4.0-1117.124~18.04.1USN-6417-1

linux-bluefieldUbuntu

Fixed in:5.4.0-1072.78USN-6417-1

linux-gcpUbuntu

Fixed in:5.4.0-1115.124USN-6417-1

linux-gcp-5.11Ubuntu

Fixed in:5.11.0-1029.33~20.04.3USN-5265-1

linux-gcp-5.4Ubuntu

Fixed in:5.4.0-1115.124~18.04.1USN-6417-1

linux-gkeopUbuntu

Fixed in:5.4.0-1078.82USN-6417-1

linux-hwe-5.13Ubuntu

Fixed in:5.13.0-28.31~20.04.1USN-5265-1

linux-hwe-5.4Ubuntu

Fixed in:5.4.0-164.181~18.04.1USN-6417-1

linux-ibmUbuntu

Fixed in:5.4.0-1058.63USN-6417-1

linux-ibm-5.4Ubuntu

Fixed in:5.4.0-1058.63~18.04.1USN-6417-1

linux-image-5.10.0-1053-oemUbuntu

Fixed in:5.10.0-1053.55USN-5207-1

linux-image-5.11.0-1028-azureUbuntu

Fixed in:5.11.0-1028.31~20.04.2USN-5265-1

linux-image-5.11.0-1028-oracleUbuntu

Fixed in:5.11.0-1028.31~20.04.1USN-5265-1

linux-image-5.11.0-1029-gcpUbuntu

Fixed in:5.11.0-1029.33~20.04.3USN-5265-1

linux-image-5.13.0-1029-oemUbuntu

Fixed in:5.13.0-1029.36USN-5265-1

linux-image-5.13.0-28-genericUbuntu

Fixed in:5.13.0-28.31~20.04.1USN-5265-1

linux-image-5.13.0-28-generic-64kUbuntu

Fixed in:5.13.0-28.31~20.04.1USN-5265-1

linux-image-5.13.0-28-generic-lpaeUbuntu

Fixed in:5.13.0-28.31~20.04.1USN-5265-1

linux-image-5.13.0-28-lowlatencyUbuntu

Fixed in:5.13.0-28.31~20.04.1USN-5265-1

linux-image-5.14.0-1022-oemUbuntu

Fixed in:5.14.0-1022.24USN-5278-1

linux-image-5.4.0-1023-iotUbuntu

Fixed in:5.4.0-1023.24USN-6417-1

linux-image-5.4.0-1031-xilinx-zynqmpUbuntu

Fixed in:5.4.0-1031.35USN-6417-1

linux-image-5.4.0-1058-ibmUbuntu

Fixed in:5.4.0-1058.63~18.04.1USN-6417-1

Fixed in:5.4.0-1058.63USN-6417-1

linux-image-5.4.0-1072-bluefieldUbuntu

Fixed in:5.4.0-1072.78USN-6417-1

linux-image-5.4.0-1078-gkeopUbuntu

Fixed in:5.4.0-1078.82USN-6417-1

linux-image-5.4.0-1095-raspiUbuntu

Fixed in:5.4.0-1095.106~18.04.1USN-6417-1

Fixed in:5.4.0-1095.106USN-6417-1

linux-image-5.4.0-1100-kvmUbuntu

Fixed in:5.4.0-1100.106USN-6417-1

linux-image-5.4.0-1110-oracleUbuntu

Fixed in:5.4.0-1110.119~18.04.1USN-6417-1

Fixed in:5.4.0-1110.119USN-6417-1

linux-image-5.4.0-1111-awsUbuntu

Fixed in:5.4.0-1111.120~18.04.1USN-6417-1

Fixed in:5.4.0-1111.120USN-6417-1

linux-image-5.4.0-1115-gcpUbuntu

Fixed in:5.4.0-1115.124~18.04.1USN-6417-1

Fixed in:5.4.0-1115.124USN-6417-1

linux-image-5.4.0-1117-azureUbuntu

Fixed in:5.4.0-1117.124~18.04.1USN-6417-1

Fixed in:5.4.0-1117.124USN-6417-1

linux-image-5.4.0-164-genericUbuntu

Fixed in:5.4.0-164.181~18.04.1USN-6417-1

Fixed in:5.4.0-164.181USN-6417-1

linux-image-5.4.0-164-generic-lpaeUbuntu

Fixed in:5.4.0-164.181USN-6417-1

linux-image-5.4.0-164-lowlatencyUbuntu

Fixed in:5.4.0-164.181~18.04.1USN-6417-1

Fixed in:5.4.0-164.181USN-6417-1

linux-image-awsUbuntu

Fixed in:5.4.0.1111.89USN-6417-1

Fixed in:5.11.0.1028.31~20.04.26USN-5265-1

linux-image-aws-lts-20.04Ubuntu

Fixed in:5.4.0.1111.108USN-6417-1

linux-image-azureUbuntu

Fixed in:5.4.0.1117.90USN-6417-1

Fixed in:5.11.0.1028.31~20.04.26USN-5265-1

linux-image-azure-lts-20.04Ubuntu

Fixed in:5.4.0.1117.110USN-6417-1

linux-image-bluefieldUbuntu

Fixed in:5.4.0.1072.67USN-6417-1

linux-image-gcpUbuntu

Fixed in:5.4.0.1115.91USN-6417-1

Fixed in:5.11.0.1029.33~20.04.27USN-5265-1

linux-image-gcp-lts-20.04Ubuntu

Fixed in:5.4.0.1115.117USN-6417-1

linux-image-genericUbuntu

Fixed in:5.4.0.164.161USN-6417-1

linux-image-generic-64k-hwe-20.04Ubuntu

Fixed in:5.13.0.28.31~20.04.15USN-5265-1

linux-image-generic-hwe-18.04Ubuntu

Fixed in:5.4.0.164.181~18.04.131USN-6417-1

linux-image-generic-hwe-20.04Ubuntu

Fixed in:5.13.0.28.31~20.04.15USN-5265-1

linux-image-generic-lpaeUbuntu

Fixed in:5.4.0.164.161USN-6417-1

linux-image-generic-lpae-hwe-20.04Ubuntu

Fixed in:5.13.0.28.31~20.04.15USN-5265-1

linux-image-gkeopUbuntu

Fixed in:5.4.0.1078.76USN-6417-1

linux-image-gkeop-5.4Ubuntu

Fixed in:5.4.0.1078.76USN-6417-1

linux-image-ibmUbuntu

Fixed in:5.4.0.1058.69USN-6417-1

linux-image-ibm-lts-20.04Ubuntu

Fixed in:5.4.0.1058.87USN-6417-1

linux-image-kvmUbuntu

Fixed in:5.4.0.1100.95USN-6417-1

linux-image-lowlatencyUbuntu

Fixed in:5.4.0.164.161USN-6417-1

linux-image-lowlatency-hwe-18.04Ubuntu

Fixed in:5.4.0.164.181~18.04.131USN-6417-1

linux-image-lowlatency-hwe-20.04Ubuntu

Fixed in:5.13.0.28.31~20.04.15USN-5265-1

linux-image-oemUbuntu

Fixed in:5.4.0.164.181~18.04.131USN-6417-1

Fixed in:5.4.0.164.161USN-6417-1

linux-image-oem-20.04Ubuntu

Fixed in:5.10.0.1053.55USN-5207-1

linux-image-oem-20.04bUbuntu

Fixed in:5.10.0.1053.55USN-5207-1

linux-image-oem-20.04cUbuntu

Fixed in:5.13.0.1029.31USN-5265-1

linux-image-oem-20.04dUbuntu

Fixed in:5.14.0.1022.19USN-5278-1

linux-image-oem-osp1Ubuntu

Fixed in:5.4.0.164.181~18.04.131USN-6417-1

Fixed in:5.4.0.164.161USN-6417-1

linux-image-oracleUbuntu

Fixed in:5.4.0.1110.119~18.04.82USN-6417-1

Fixed in:5.11.0.1028.31~20.04.20USN-5265-1

linux-image-oracle-lts-20.04Ubuntu

Fixed in:5.4.0.1110.103USN-6417-1

linux-image-raspiUbuntu

Fixed in:5.4.0.1095.125USN-6417-1

linux-image-raspi-hwe-18.04Ubuntu

Fixed in:5.4.0.1095.92USN-6417-1

linux-image-raspi2Ubuntu

Fixed in:5.4.0.1095.125USN-6417-1

linux-image-snapdragon-hwe-18.04Ubuntu

Fixed in:5.4.0.164.181~18.04.131USN-6417-1

linux-image-virtualUbuntu

Fixed in:5.4.0.164.161USN-6417-1

linux-image-virtual-hwe-18.04Ubuntu

Fixed in:5.4.0.164.181~18.04.131USN-6417-1

linux-image-virtual-hwe-20.04Ubuntu

Fixed in:5.13.0.28.31~20.04.15USN-5265-1

linux-image-xilinx-zynqmpUbuntu

Fixed in:5.4.0.1031.32USN-6417-1

linux-iotUbuntu

Fixed in:5.4.0-1023.24USN-6417-1

linux-kvmUbuntu

Fixed in:5.4.0-1100.106USN-6417-1

linux-oem-5.10Ubuntu

Fixed in:5.10.0-1053.55USN-5207-1

linux-oem-5.13Ubuntu

Fixed in:5.13.0-1029.36USN-5265-1

linux-oem-5.14Ubuntu

Fixed in:5.14.0-1022.24USN-5278-1

linux-oracleUbuntu

Fixed in:5.4.0-1110.119USN-6417-1

linux-oracle-5.11Ubuntu

Fixed in:5.11.0-1028.31~20.04.1USN-5265-1

linux-oracle-5.4Ubuntu

Fixed in:5.4.0-1110.119~18.04.1USN-6417-1

linux-raspiUbuntu

Fixed in:5.4.0-1095.106USN-6417-1

linux-raspi-5.4Ubuntu

Fixed in:5.4.0-1095.106~18.04.1USN-6417-1

linux-xilinx-zynqmpUbuntu

Fixed in:5.4.0-1031.35USN-6417-1

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorLocal

Attack ComplexityHigh

Privileges RequiredHigh

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityNone

IntegrityHigh

AvailabilityNone

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

Exploit Intelligence

0.19%probability of exploitation in 30 days

8thpercentile

Low risk: more likely to be exploited than 8% of all known CVEs.

References

Patch2

Related Vulnerabilities

Other CWE-367 (TOCTOU Race Condition) vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2022-36980	High	8.1	83%	-	Fix
CVE-2024-30088	High	7.0	68%	KEV + Ransom	Fix
CVE-2004-0594	Medium	5.1	55%	-	Fix
CVE-2024-50379	Critical	9.8	44%	-	Fix
CVE-2023-38146	High	8.8	39%	-	Fix
CVE-2024-0132	Critical	9.0	37%	-	Fix

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2024-11-21.