CVE-2021-3672

mediumpriority · track · 23EPSS 0.028 · 86 %ileDEEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

2.81% (86th) EPSS

CVSS 6.8 · medium

Is it mine?

71 products

Check your exposure

Who says so?

7 sources

cnnvd · enisa_euvd · fstec_bdu · osv

EPSS · scored 2026-10-27

A flaw was found in c-ares library, where a missing input validation check of host names returned by DNS (Domain Name Servers) can lead to output of wrong hostnames which might potentially lead to Domain Hijacking. The highest threat from this vulnerability is to confidentiality and integrity as well as system availability.

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

FixedSINEC INSsiemens_psirt
Update to V1.0.1.1 or later version
https://support.industry.siemens.com/cs/ww/en/view/109806100/
FixedSINEC INScisa_csaf_ot
Update to V1.0.1.1 or later version
https://support.industry.siemens.com/cs/ww/en/view/109806100/

cvss

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

6.8

010

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

v2.06.8mediumAV:N/AC:M/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 8.6 · impact 6.4

v3.15.6mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:Lprimary · NVD / NIST USexploitability 2.2 · impact 3.4

v3.15.6mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:O/RC:Csecondary · CISA US

v3.15.6mediumAV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:Lsecondary · FSTEC (BDU) RU

v3.15.6mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:O/RC:Csecondary · Siemens ProductCERT DE

v3.15.1mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-79USprimaryCWE-79USCWE-79USCWE-79US

affected products (71)

Products and version ranges known to be affected.

Amazon Linux 2all versionscert_bundDEcpe:/o:amazon:linux_2:-
Dell Secure Connect Gateway <5.36.00.16all versionscert_bundDE
F5 BIG-IPall versionscert_bundDEcpe:/a:f5:big-ip:-
Open Source Kibana <7.14.1all versionscert_bundDE
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:-
Dell Secure Connect Gateway< 5.36.00.16cert_bundDE
Open Source Kibana< 7.14.1cert_bundDE
SINEC INSall versionscisa_csaf_otUS
Siemens SINEC INS< V1.0.1.1cisa_csaf_otUS
n/a c-ares≤ c-ares 1.17.2enisa_euvdEU
АО «ИВК» Альт 8 СПall versionsfstec_bduRU
АО «Концерн ВНИИНС» ОС ОН «Стрелец»≤ 16.01.2023fstec_bduRU
АО «НППКТ» ОСОН ОСнова Оnyx≤ 2.1fstec_bduRU
АО «НТЦ ИТ РОСА» ROSA Virtualization≤ 2.1fstec_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 «РусБИТех-Астра» Astra Linux Special Edition для «Эльбрус»≤ 8.1 «Ленинград»fstec_bduRU

showing 20 of 71

advisories (8)

Vendor and ecosystem advisories describing this.

SSA-389290SSA-389290: Third-Party Component Vulnerabilities in SINEC INS2022-03-08csaf · siemens_psirtDE
71 vulnerabilities in third-party components as Node.js, cURL, SQLite, CivetWeb and DNS(ISC BIND) could allow an attacker to interfere with the affected product in various ways. Siemens has released an update for SINEC INS and recommends to update to the latest versions.
WID-SEC-W-2022-0029Elasticsearch und Kibana: Mehrere SchwachstellenDeutsch2021-09-01csaf · cert_bundDE
Ein entfernter, authentisierter Angreifer kann mehrere Schwachstellen in Elasticsearch und Kibana ausnutzen, um beliebigen Programmcode auszuführen, um Informationen offenzulegen, um einen Cross-Site Scripting Angriff durchzuführen und um Administratorrechte zu erlangen.
WID-SEC-W-2023-0856IBM QRadar SIEM: Mehrere SchwachstellenDeutsch2022-05-31csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in IBM QRadar SIEM ausnutzen, um die Vertraulichkeit, Integrität und Verfügbarkeit zu gefährden.
WID-SEC-W-2023-1614Tenable Security Nessus Network Monitor: Mehrere SchwachstellenDeutsch2023-06-29csaf · cert_bundDE
Ein entfernter, anonymer, authentisierter oder lokaler Angreifer kann mehrere Schwachstellen in Tenable Security Nessus Network Monitor ausnutzen, um beliebigen Code auszuführen, vertrauliche Informationen offenzulegen, einen Denial-of-Service-Zustand auszulösen und Daten zu manipulieren.
ICSA-22-069-09Siemens SINEC INS2022-03-08icsa · cisa_csaf_otUS
71 vulnerabilities in third-party components as Node.js, cURL, SQLite, CivetWeb and DNS(ISC BIND) could allow an attacker to interfere with the affected product in various ways. Siemens has released an update for SINEC INS and recommends to update to the latest versions.
BIT-node-2021-36722024-03-06vendor · osvUS
A flaw was found in c-ares library, where a missing input validation check of host names returned by DNS (Domain Name Servers) can lead to output of wrong hostnames which might potentially lead to Domain Hijacking. The highest threat from this vulnerability is to confidentiality and integrity as well as system availability.
BIT-node-min-2021-36722024-12-16vendor · osvUS
A flaw was found in c-ares library, where a missing input validation check of host names returned by DNS (Domain Name Servers) can lead to output of wrong hostnames which might potentially lead to Domain Hijacking. The highest threat from this vulnerability is to confidentiality and integrity as well as system availability.
BIT-pgbouncer-2021-36722024-03-06vendor · osvUS
A flaw was found in c-ares library, where a missing input validation check of host names returned by DNS (Domain Name Servers) can lead to output of wrong hostnames which might potentially lead to Domain Hijacking. The highest threat from this vulnerability is to confidentiality and integrity as well as system availability.

also known as (7)

Other names and identifiers for this entity.

CNNVD-202108-883 cnnvd
EUVD-2021-26964 enisa_euvd
BDU:2022-00342 fstec_bdu
GHSA-hghm-3vc3-hppj enisa_euvd
BIT-node-2021-3672osv
BIT-node-min-2021-3672osv
BIT-pgbouncer-2021-3672osv

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu osv cert_bund cisa_csaf_ot siemens_psirt NVD CVE.org MITRE

published 2021-11-23modified 2026-06-17

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+53003 more

references (51)

External citations — patches, advisories, analysis.

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