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Full vulnerability report · 2021
CVE-2021-3672High confidence

n/a c-ares — Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

n/a · c-ares

5.6MediumCVSS 3.1
Recommended action
Within 7 days

Medium technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.

Patch available
Direct vendor intelligence

Authoritative vendor CSAF and VEX advisories

Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.

1 current
SSA-389290 · CSAF 2.0 · revision 1 · finalSiemens ProductCERTSSA-389290: Third-Party Component Vulnerabilities in SINEC INS
1 known affected

The vendor explicitly identifies these products as affected by this CVE.

  • SINEC INS
Summary
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.
Remediation
Update to V1.0.1.1 or later version
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Select the national-authority views to include. The exact source language is shown on each matched advisory. Your choice is remembered on this device and encoded in the shareable URL.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2021-26964

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionWithin 7 days

Medium technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.

Patch available
01

What, why and how

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.

What

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.

Why

Attacker-controlled content can reach a browser as executable script without sufficient output encoding or sanitisation.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

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.

Why

Attacker-controlled content can reach a browser as executable script without sufficient output encoding or sanitisation.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
Reference recorded

A structured CVE source labels at least one public reference as exploit material. BlackTree has not independently validated that it is safe, reliable or weaponised.

Likely attack path
a network path → Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
High: exploitation depends on specific conditions
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-79

CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting'). The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACHighAttack complexity: Successful exploitation depends on specific conditions outside the attacker's direct control.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CLowConfidentiality impact: A successful attack can cause a limited loss.ILowIntegrity impact: A successful attack can cause a limited loss.ALowAvailability impact: A successful attack can cause a limited loss.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
NetworkUnauthenticatedCWE-79Public exploit reference
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

BSI · German · WID-SEC-W-2023-1614Tenable Security Nessus Network Monitor: Mehrere Schwachstellen

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.

Official advisory
BSI · German · WID-SEC-W-2023-0856IBM QRadar SIEM: Mehrere Schwachstellen

Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in IBM QRadar SIEM ausnutzen, um die Vertraulichkeit, Integrität und Verfügbarkeit zu gefährden.

Official advisory
BSI · German · WID-SEC-W-2022-0029Elasticsearch und Kibana: Mehrere Schwachstellen

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.

Official advisory
CERT-FR · French · CERTFR-2023-AVI-0499Multiples vulnérabilités dans Tenable Nessus Network Monitor

/CVERecord?id=CVE-2020-9327 Référence CVE CVE-2021-20227 https://www.cve.org/CVERecord?id=CVE-2021-20227 Référence CVE CVE-2021-30560 https://www.cve.org/CVERecord?id=CVE-2021-30560 Référence CVE CVE-2021-31239 https://www.cve.org/CVERecord?id=CVE-2021-31239 Référence CVE CVE-2021-3517 https://www.cve.org/CVERecord?id=CVE-2021-3517 Référence CVE CVE-2021-3518 https://www.cve.org/CVERecord?id=CVE-2021-3518 Référence CVE CVE-2021-3537 https://www.cve.org/CVERecord?id=CVE-2021-3537 Référence CVE CVE-2021-3541 https://www.cve.org/CVERecord?id=CVE-2021-3541 Référence CVE CVE-2021-36690 https://www.cve.org/CVERecord?id=CVE-2021-36690 Référence CVE CVE-2021-3672 https://www.cve.org/CVERecord?id=CVE-2021-3672 Référence CVE CVE-2021-45346 https://www.cve.org/CVERecord?id=CVE-2021-45346 Référence CVE CVE-2022-22576 https://www.cve.org/CVERecord?id=CVE-2022-22576 Référence CVE CVE-2022-23308 https://www.cve.org/CVERecord?id=CVE-2022-23308 Référence CVE CVE-2022-23395 https://www.cve.org/CVERecord?id=CVE-2022-23395 Référence CVE CVE-2022-27774 https://www.cve.org/CVERecord?id=CVE-2022-27774 Référence CVE CVE-2022-27775 https://www.cve.org/CVERecord?id=CVE-2022-27775 Référence CVE CVE-2022-27776 https://www.cve.org/CVERecord?id=CVE-2022-27776 Référence CVE CVE-2022-27781 https://www.cve.org/CVERecord?id=C

Official advisory
CERT-FR · French · CERTFR-2022-AVI-510Multiples vulnérabilités dans IBM QRadar

d?id=CVE-2021-22931 Référence CVE CVE-2021-22939 https://www.cve.org/CVERecord?id=CVE-2021-22939 Référence CVE CVE-2021-22940 https://www.cve.org/CVERecord?id=CVE-2021-22940 Référence CVE CVE-2021-23343 https://www.cve.org/CVERecord?id=CVE-2021-23343 Référence CVE CVE-2021-23362 https://www.cve.org/CVERecord?id=CVE-2021-23362 Référence CVE CVE-2021-27290 https://www.cve.org/CVERecord?id=CVE-2021-27290 Référence CVE CVE-2021-32803 https://www.cve.org/CVERecord?id=CVE-2021-32803 Référence CVE CVE-2021-32804 https://www.cve.org/CVERecord?id=CVE-2021-32804 Référence CVE CVE-2021-33502 https://www.cve.org/CVERecord?id=CVE-2021-33502 Référence CVE CVE-2021-3672 https://www.cve.org/CVERecord?id=CVE-2021-3672 Référence CVE CVE-2021-37701 https://www.cve.org/CVERecord?id=CVE-2021-37701 Référence CVE CVE-2021-37712 https://www.cve.org/CVERecord?id=CVE-2021-37712 Référence CVE CVE-2021-37713 https://www.cve.org/CVERecord?id=CVE-2021-37713 Référence CVE CVE-2021-3807 https://www.cve.org/CVERecord?id=CVE-2021-3807 Référence CVE CVE-2021-3918 https://www.cve.org/CVERecord?id=CVE-2021-3918 Gestion détaillée du document le 01 juin 2022 Version initiale Alertes Avis Bulletins d’actualités Mentions légales Conditions générales À propos Contact cyber.gouv.fr service-public.fr legifrance.gouv.fr info.gouv.fr fra

Official advisory
CERT-FR · French · CERTFR-2022-AVI-216Multiples vulnérabilités dans les produits Siemens

ecord?id=CVE-2021-32938 Référence CVE CVE-2021-32940 https://www.cve.org/CVERecord?id=CVE-2021-32940 Référence CVE CVE-2021-32944 https://www.cve.org/CVERecord?id=CVE-2021-32944 Référence CVE CVE-2021-32946 https://www.cve.org/CVERecord?id=CVE-2021-32946 Référence CVE CVE-2021-32948 https://www.cve.org/CVERecord?id=CVE-2021-32948 Référence CVE CVE-2021-32950 https://www.cve.org/CVERecord?id=CVE-2021-32950 Référence CVE CVE-2021-32952 https://www.cve.org/CVERecord?id=CVE-2021-32952 Référence CVE CVE-2021-3449 https://www.cve.org/CVERecord?id=CVE-2021-3449 Référence CVE CVE-2021-3450 https://www.cve.org/CVERecord?id=CVE-2021-3450 Référence CVE CVE-2021-3672 https://www.cve.org/CVERecord?id=CVE-2021-3672 Référence CVE CVE-2021-3711 https://www.cve.org/CVERecord?id=CVE-2021-3711 Référence CVE CVE-2021-3712 https://www.cve.org/CVERecord?id=CVE-2021-3712 Référence CVE CVE-2021-37208 https://www.cve.org/CVERecord?id=CVE-2021-37208 Référence CVE CVE-2021-37209 https://www.cve.org/CVERecord?id=CVE-2021-37209 Référence CVE CVE-2021-37701 https://www.cve.org/CVERecord?id=CVE-2021-37701 Référence CVE CVE-2021-37712 https://www.cve.org/CVERecord?id=CVE-2021-37712 Référence CVE CVE-2021-37713 https://www.cve.org/CVERecord?id=CVE-2021-37713 Référence CVE CVE-2021-39134 https://www.cve.org/CVERecord?id=CVE-2

Official advisory
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Patch available
Affected
SINEC INS
Fixed
An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
Action
Update to V1.0.1.1 or later version
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 23 Nov 2021 · Last source change 15 Oct 2024, 17:14 UTC · CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CVE recordCVE.org · 5.1
CVSS sourceNIST NVD
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2021-26964
Product sourceVendor CSAF · Siemens ProductCERT
Remediation sourceVendor CSAF · Siemens ProductCERT
CWE sourceCNA
NVD statusNVD modified after enrichment

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates →

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2021-3672 · cve.blacktree.nl