CVE-2021-20322

mediumpriority · track · 32OT risk · elevatedEPSS 0.069 · 94 %ileDEEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

6.90% (94th) EPSS

CVSS 5.8 · medium

Is it mine?

54 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

A flaw in the processing of received ICMP errors (ICMP fragment needed and ICMP redirect) in the Linux kernel functionality was found to allow the ability to quickly scan open UDP ports. This flaw allows an off-path remote user to effectively bypass the source port UDP randomization. The highest threat from this vulnerability is to confidentiality and possibly integrity, because software that relies on UDP source port randomization are indirectly affected as well.

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 · 5.8–7.4

v2.05.8mediumAV:N/AC:M/Au:N/C:P/I:P/A:Nprimary · NVD / NIST USexploitability 8.6 · impact 4.9

v3.17.4highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:Nprimary · NVD / NIST USexploitability 2.2 · impact 5.2

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

v3.16.8mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-330USprimaryCWE-330US

affected products (54)

Products and version ranges known to be affected.

Amazon Linux 2all versionscert_bundDEcpe:/o:amazon:linux_2:-
Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
Open Source Linux Kernelall versionscert_bundDEcpe:/o:linux:linux_kernel:-
Oracle Linuxall versionscert_bundDEcpe:/o:oracle:linux:-
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 Kernel4.15 → 4.19.215enisa_euvdEU
n/a Kernel4.20 → 5.4.146enisa_euvdEU
n/a Kernel5.11 → 5.13.17enisa_euvdEU
n/a Kernel5.14 → 5.14.4enisa_euvdEU
n/a Kernel5.5 → 5.10.65enisa_euvdEU
IBM Corp. Elastic Storage System≤ 6.1.4.0fstec_bduRU
IBM Corp. Elastic Storage System≤ 6.1.2.4fstec_bduRU
Red Hat Inc. Red Hat Enterprise Linux≤ 8fstec_bduRU
ООО "Открытая мобильная платформа" ОС Аврора≤ 4.0.2fstec_bduRU
ООО "Открытая мобильная платформа" ОС Аврора≤ 4.0.2.172fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 4.7fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 1.7fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 1.6 «Смоленск»fstec_bduRU

showing 20 of 54

advisories (2)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2022-0231Linux Kernel: Schwachstelle ermöglicht Offenlegung von InformationenDeutsch2021-12-14csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann eine Schwachstelle im Linux Kernel ausnutzen, um Informationen offenzulegen.
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.

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 CVE.org MITRE

published 2022-02-18modified 2026-07-30

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references (54)

External citations — patches, advisories, analysis.

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