CVE-2021-3671

mediumpriority · track · 27EPSS 0.021 · 82 %ileDEEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

2.12% (82nd) EPSS

CVSS 4 · medium

Is it mine?

27 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

A null pointer de-reference was found in the way samba kerberos server handled missing sname in TGS-REQ (Ticket Granting Server - Request). An authenticated user could use this flaw to crash the samba server.

cvss

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

6.5

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.04mediumAV:N/AC:L/Au:S/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 8 · impact 2.9

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 3.6

v3.16.5mediumAV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU

v3.16mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-476USprimaryCWE-476US

affected products (27)

Products and version ranges known to be affected.

Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
Open Source Heimdal < 7.7.1all versionscert_bundDEcpe:/a:heimdal:heimdal:7.7.1
Open Source Heimdal < 7.8.0all versionscert_bundDEcpe:/a:heimdal:heimdal:7.8.0
Ubuntu Linuxall versionscert_bundDEcpe:/o:canonical:ubuntu_linux:-
n/a Samba≤ Fixed in samba 4.13.12, samba 4.14.8enisa_euvdEU
Canonical Ltd. Ubuntu≤ 16.04 ESMfstec_bduRU
Canonical Ltd. Ubuntu≤ 21.10fstec_bduRU
Canonical Ltd. Ubuntu≤ 21.04fstec_bduRU
Canonical Ltd. Ubuntu≤ 20.04 LTSfstec_bduRU
Canonical Ltd. Ubuntu≤ 14.04 ESMfstec_bduRU
Canonical Ltd. Ubuntu≤ 18.04 LTSfstec_bduRU
Samba Team Samba≤ 4.13.12fstec_bduRU
Samba Team Samba4.14.0 → 4.14.8fstec_bduRU
АО «НППКТ» ОСОН ОСнова Оnyx≤ 2.5fstec_bduRU
АО «НТЦ ИТ РОСА» ROSA Virtualization≤ 2.1fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 4.7fstec_bduRU
ООО «Юбитех» UBLinux≤ 2204fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 11fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 10fstec_bduRU
Сообщество свободного программного обеспечения Heimdal≤ 7.7.0fstec_bduRU

showing 20 of 27

advisories (2)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2022-1714Samba: Mehrere Schwachstellen ermöglichen Denial of ServiceDeutsch2021-10-05csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Samba ausnutzen, um einen Denial of Service Angriff durchzuführen.
WID-SEC-W-2022-2372genua genugate: Mehrere SchwachstellenDeutsch2022-12-19csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann einige der mehreren Schwachstellen in Komponenten von Drittanbietern ausnutzen, die von genua genugate verwendet werden, um Informationen offenzulegen und potentiell weitere, unbekannte Auswirkungen zu erzielen.

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 2021-10-12modified 2026-06-17

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+8817 more

references (35)

External citations — patches, advisories, analysis.

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