CVE-2021-4204

highpriority · track · 38EPSS 0.012 · 69 %ileexploit · PoCDEEURUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

1 exploit · PoC

Likely / severe?

1.23% (69th) EPSS

CVSS 7.1 · high

Is it mine?

25 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-26

An out-of-bounds (OOB) memory access flaw was found in the Linux kernel's eBPF due to an Improper Input Validation. This flaw allows a local attacker with a special privilege to crash the system or leak internal information.

cvss

Technical severity, 0–10. One row per scoring source.

7.1

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.7–7.1

v3.17.1highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:Hprimary · NVD / NIST USexploitability 1.8 · impact 5.2

v3.17.1highAV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:Hsecondary · FSTEC (BDU) RU

v3.16.7mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H/E:Psecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-119USprimaryCWE-119USCWE-20USCWE-20USCWE-787US

exploits (1)

Public proof-of-concept and weaponised exploit code.

tr3ee/CVE-2021-4204CVE-2021-4204: Linux Kernel eBPF Local Privilege EscalationPoC · poc_in_github

affected products (25)

Products and version ranges known to be affected.

IBM DB2 on Cloud Pak for Dataall versionscert_bundDEcpe:/a:ibm:db2:on_cloud_pak_for_data
IBM QRadar SIEMall versionscert_bundDEcpe:/a:ibm:qradar_siem:-
Open Source Linux Kernelall versionscert_bundDEcpe:/o:linux:linux_kernel:-
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
SUSE Linuxall versionscert_bundDEcpe:/o:suse:suse_linux:-
Ubuntu Linuxall versionscert_bundDEcpe:/o:canonical:ubuntu_linux:-
n/a Kernel≤ Affects Linux kernel v5.8 or laterenisa_euvdEU
Canonical Ltd. Ubuntu≤ 20.04 LTSfstec_bduRU
Red Hat Inc. Red Hat Enterprise Linux≤ 9fstec_bduRU
АО «НППКТ» ОСОН ОСнова Оnyx≤ 2.7fstec_bduRU
АО «НТЦ ИТ РОСА» ROSA Virtualization 3.0≤ 3.0fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 1.6 «Смоленск»fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 1.7fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 4.7fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 11fstec_bduRU
Сообщество свободного программного обеспечения Linux5.8 → 5.17fstec_bduRU
debian debian linux= 11.0nvdUScpe:2.3:o:debian:debian_linux:*:*:*:*:*:*:*:*
linux linux kernel< 5.8.0nvdUScpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux kernel= 5.8.0nvdUScpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
netapp h300s firmwareall versionsnvdUScpe:2.3:o:netapp:h300s_firmware:*:*:*:*:*:*:*:*

showing 20 of 25

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2022-0790Linux Kernel: Mehrere Schwachstellen ermöglichen CodeausführungDeutsch2022-01-10csaf · cert_bundDE
Ein lokaler Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um beliebigen Programmcode auszuführen und um einen Denial of Service Zustand herbeizuführen.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund nvd NVD CVE.org MITRE

published 2022-08-24modified 2026-06-17

related (21,028)

Related entries.

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+21023 more

references (21)

External citations — patches, advisories, analysis.

scry

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