Exploitation de fond Catalogue KEV Rançongiciel Sans authentification
CVE-2021-40444

Microsoft MSHTML Remote Code Execution Vulnerability

Microsoft is investigating reports of a remote code execution vulnerability in MSHTML that affects Microsoft Windows. Microsoft is aware of targeted attacks that attempt to exploit this vulnerability by using specially-crafted Microsoft…

Indice de priorité CheckOps
9,5/10 Corriger sous 24 h
Gravité8,8
Probabilité9,8
Exploitation5/5

Gravité = CVSS. Probabilité = EPSS (FIRST). Exploitation = signaux publics : KEV, EUVD, rançongiciel, EPSS au-dessus de 10 %, accès sans compte.

EPSS · aujourd’hui 97,8 % plus haute que 99,9 % des CVE
CVSS 3.1 8,8 AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:
Exploitée depuis 1 826 jours 03/11/2021
Échéance CISA 17/11/2021 pour les agences fédérales américaines

Probabilité d’exploitation EPSS · FIRST

05010026/0905/1015/1024/1002/11
Probabilité EPSS (%)Percentile parmi toutes les CVE

Signaux d’exploitation 5 / 5

  • Catalogue KEV (CISA)03/11/2021
  • EUVD exploitée (ENISA)03/11/2021
  • Utilisée par des rançongicielsoui
  • EPSS au-dessus de 10 %97,8 %
  • Sans compte, par le réseauoui

Que faire

Corriger

Appliquer le correctif de l’éditeur dès qu’il est disponible.

Consigne de la CISA : Apply updates per vendor instructions.

En attendant

Retirer le service d’internet ou en filtrer l’accès, surveiller les journaux et chercher des traces de compromission.

Éditeurs (CRA)

Faille exploitée dans votre produit : alerte précoce à l’ENISA sous 24 h, puis notification sous 72 h (article 14 du Cyber Resilience Act). Le CRA expliqué

Description ENISA EUVD

Microsoft is investigating reports of a remote code execution vulnerability in MSHTML that affects Microsoft Windows. Microsoft is aware of targeted attacks that attempt to exploit this vulnerability by using specially-crafted Microsoft Office documents. An attacker could craft a malicious ActiveX control to be used by a Microsoft Office document that hosts the browser rendering engine. The attacker would then have to convince the user to open the malicious document. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights. Microsoft Defender Antivirus and Microsoft Defender for Endpoint both provide detection and protections for the known vulnerability. Customers should keep antimalware products up to date. Customers who utilize automatic updates do not need to take additional action. Enterprise customers who manage updates should select the detection build 1.349.22.0 or newer and deploy it across their environments. Microsoft Defender for Endpoint alerts will be displayed as: “Suspicious Cpl File Execution”. Upon completion of this investigation, Microsoft will take the appropriate action to help protect our customers. This may include providing a security update through our monthly release process or providing an out-of-cycle security update, depending on customer needs. Please see the Mitigations and Workaround sections for important information about steps you can take to protect your system from this vulnerability. UPDATE September 14, 2021: Microsoft has released security updates to address this vulnerability. Please see the Security Updates table for the applicable update for your system. We recommend that you install these updates immediately. Please see the FAQ for important information about which updates are applicable to your system.

Texte de la source, en anglais.

Produits touchés

Windows Server 2008 R2 Service Pack 1 (Server Core installation)Windows 8.1Windows Server 2019 (Server Core installation)Windows 10 Version 20H2Windows Server 2012Windows 10 Version 2004Windows Server 2019Windows Server version 20H2Windows Server 2012 R2 (Server Core installation)Windows Server 2012 (Server Core installation)Windows Server version 2004Windows Server 2008 Service Pack 2 (Server Core installation)Windows 10 Version 21H1Windows 10 Version 1809Windows Server 2008 R2 Service Pack 1Windows Server 2016Windows 10 Version 1607Windows Server 2016 (Server Core installation)Windows Server 2022Windows 10 Version 1507Windows 7 Service Pack 1Windows 7Windows 10 Version 1909Windows Server 2008 Service Pack 2Windows Server 2012 R2MSHTML
Versions touchées
  • 6.1.7601.0 <6.1.7601.25712
  • 6.3.0 <6.3.9600.20120
  • 10.0.17763.0 <10.0.17763.2183
  • 10.0.0 <10.0.19042.1237
  • 6.2.9200.0 <6.2.9200.23462
  • 10.0.0 <10.0.19041.1237
  • 6.3.9600.0 <6.3.9600.20120
  • 6.0.6003.0 <6.0.6003.21218
  • 10.0.0 <10.0.19043.1237
  • 10.0.14393.0 <10.0.14393.4651
  • 10.0.20348.0 <10.0.20348.230
  • 10.0.10240.0 <10.0.10240.19060
Faiblesses (CWE)

Paquets open source OSV

Bibliothèques touchées selon OSV, avec les versions corrigées.

Chronologie

  1. Publication

  2. Exploitation signalée (ENISA)

  3. Ajout au catalogue KEV

  4. Échéance de correction CISA

  5. EPSS au plus haut : 97,8 %

Références

Autres failles exploitées du même éditeur

  • CVE-2026-96951Microsoft Windows Command Injection Vulnerability
    5,6 · Exploitation active
  • CVE-2026-65660Microsoft SharePoint Code Injection Vulnerability
    5,0 · Exploitation active
  • CVE-2026-85880Microsoft Windows Heap-Based Buffer Overflow Vulnerability
    4,3 · Exploitation active
  • CVE-2026-81963Microsoft Windows Link Following Vulnerability
    4,3 · Exploitation active
  • CVE-2019-1068Microsoft SQL Server Remote Code Execution Vulnerability
    7,0 · Exploitation active
  • CVE-2026-69836Microsoft Entra
    5,3 · Exploitation active

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Sources : CISA KEV · ENISA EUVD · FIRST EPSS · OSV. Données publiques agrégées par CheckOps, mises à jour automatiquement. Les textes des sources restent la propriété de leurs auteurs. Toutes les failles exploitées