CVE-2021-4083

mediumpriority · track · 28EPSS 0.003 · 24 %ileDEEUFRRUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.31% (24th) EPSS

CVSS 6.9 · medium

Is it mine?

46 products

Check your exposure

Who says so?

6 sources

cnnvd · enisa_euvd · fstec_bdu · osv

EPSS · scored 2026-10-27

A read-after-free memory flaw was found in the Linux kernel's garbage collection for Unix domain socket file handlers in the way users call close() and fget() simultaneously and can potentially trigger a race condition. This flaw allows a local user to crash the system or escalate their privileges on the system. This flaw affects Linux kernel versions prior to 5.16-rc4.

cvss

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

7.4

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.4–7.4

v2.06.9mediumAV:L/AC:M/Au:N/C:C/I:C/A:Cprimary · NVD / NIST USexploitability 3.4 · impact 10

v3.17highCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 1 · impact 5.9

v3.17.4highAV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.16.4mediumCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-362USprimaryCWE-416USCWE-416US

affected products (46)

Products and version ranges known to be affected.

Amazon Linux 2all versionscert_bundDEcpe:/o:amazon:linux_2:-
IBM Spectrum Protect 10.1all versionscert_bundDEcpe:/a:ibm:spectrum_protect:10.1
IBM Spectrum Protect 8.1all versionscert_bundDEcpe:/a:ibm:spectrum_protect:8.1
Ubuntu Linuxall versionscert_bundDEcpe:/o:canonical:ubuntu_linux:-
n/a Kernel≤ kernel 5.16-rc4enisa_euvdEU
Red Hat Inc. Red Hat Enterprise Linux≤ 7fstec_bduRU
Red Hat Inc. Red Hat Enterprise Linux≤ 8fstec_bduRU
Red Hat Inc. Red Hat Virtualization≤ 4fstec_bduRU
АО «НППКТ» ОСОН ОСнова Оnyx≤ 2.7fstec_bduRU
ООО "Открытая мобильная платформа" ОС Аврора≤ 5.1.5fstec_bduRU
ООО "Открытая мобильная платформа" ОС Аврора≤ 3.2.3fstec_bduRU
ООО «Ред Софт» РЕД ОС≤ 7.3fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 1.7fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 1.6 «Смоленск»fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 4.7fstec_bduRU
ООО «Юбитех» UBLinux≤ 2204fstec_bduRU
Сообщество свободного программного обеспечения Linux4.0 → 4.4.293fstec_bduRU
Сообщество свободного программного обеспечения Linux4.10 → 4.14.256fstec_bduRU
Сообщество свободного программного обеспечения Linux4.15 → 4.19.219fstec_bduRU
Сообщество свободного программного обеспечения Linux4.20 → 5.4.163fstec_bduRU

showing 20 of 46

advisories (4)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2022-0515IBM Spectrum Protect: Mehrere SchwachstellenDeutsch2022-06-29csaf · cert_bundDE
Ein entfernter, anonymer, authentisierter oder lokaler Angreifer kann mehrere Schwachstellen in IBM Spectrum Protect ausnutzen, um einen Denial-of-Service-Zustand herbeizuführen, Sicherheitsmaßnahmen zu umgehen, vertrauliche Informationen offenzulegen, beliebigen Code auszuführen, seine Rechte zu erweitern oder beliebigen Code mit Root-Rechten auszuführen.
ASB-A-2164083502022-09-01vendor · osvUS
In fget() of file.c, there is a possible read after free due to a race condition. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.
CERTFR-2026-AVI-1333Multiples vulnérabilités dans le noyau Linux d'UbuntuFrançais2026-10-16vendor · certfrFR
PUB-A-2164083502022-05-01vendor · osvUS
In fget() of multiple locations, there is a possible read after free due to a race condition. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.

also known as (7)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu osv cert_bund certfr NVD CVE.org MITRE

published 2022-01-18modified 2026-06-17

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+4134 more

references (86)

External citations — patches, advisories, analysis.

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