Microsoft lanzó el día martes nuevos parches de seguridad para contener más de 70 vulnerabilidades en Windows y otro softwares, incluyendo una solución para una vulnerabilidad de escalamiento de privilegios, que ha estado siendo explotada de forma activa por actores de amenazas para tomar el control de los dispositivo infectado mediante un RAT (Remote Access Tools).
El parche del martes de octubre incluye correcciones para 4 vulnerabilidades zero-day, con una vulnerabilidad de elevación de privilegios de Win32k que se sabe ha sido explotada activamente en ataques. Microsoft clasifica una vulnerabilidad como de día cero si se divulga públicamente o sí es explotada de manera activa sin que haya una solución oficial disponible (por ahora).
La vulnerabilidad explotada activamente fue descubierta por Boris Larin (oct0xor) de equipo de Kaspersky y permite a un actor de la amenaza obtener privilegios en un dispositivo Windows.
- CVE-2021-40449 – Vulnerabilidad de elevación de privilegios en Win32k.
Kaspersky informo que la vulnerabilidad fue utilizada por actores de amenazas en «campañas de espionaje generalizadas contra empresas de TI, contratistas militares/de defensa y entidades diplomáticas». Como parte de los ataques, los actores de la amenaza instalaron un troyano de acceso remoto (RAT) que se elevó con permisos superiores utilizando la vulnerabilidad de día cero de Windows.
Kaspersky llamó a este grupo cómo MysterSnail, y se atribuye a la actividad de IronHusky y de APT de habla China.
Microsoft también corrigió otras 3 vulnerabilidades divulgadas públicamente que no se sabe sí han sido utilizadas por algún grupo de actores de amenazas.
- CVE-2021-41335 – Vulnerabilidad de elevación de privilegios en el kernel de Windows.
- CVE-2021-41338 – Vulnerabilidad en la función de seguridad de las reglas del cortafuegos de Windows AppContainer.
- CVE-2021-40469 – Vulnerabilidad de ejecución remota de código en el servidor DNS de Windows.
Tabla de vulnerabilidades corrigidas en la actualización de Octubre 2021:
| Tag | CVE ID | CVE | Importancia |
|---|---|---|---|
| .NET Core & Visual Studio | CVE-2021-41355 | .NET Core and Visual Studio Information Disclosure Vulnerability | Important |
| Active Directory Federation Services | CVE-2021-41361 | Active Directory Federation Server Spoofing Vulnerability | Important |
| Console Window Host | CVE-2021-41346 | Console Window Host Security Feature Bypass Vulnerability | Important |
| HTTP.sys | CVE-2021-26442 | Windows HTTP.sys Elevation of Privilege Vulnerability | Important |
| Microsoft DWM Core Library | CVE-2021-41339 | Microsoft DWM Core Library Elevation of Privilege Vulnerability | Important |
| Microsoft Dynamics | CVE-2021-40457 | Microsoft Dynamics 365 Customer Engagement Cross-Site Scripting Vulnerability | Important |
| Microsoft Dynamics | CVE-2021-41353 | Microsoft Dynamics 365 (on-premises) Spoofing Vulnerability | Important |
| Microsoft Dynamics | CVE-2021-41354 | Microsoft Dynamics 365 (on-premises) Cross-site Scripting Vulnerability | Important |
| Microsoft Edge (Chromium-based) | CVE-2021-37978 | Chromium: CVE-2021-37978 Heap buffer overflow in Blink | Unknown |
| Microsoft Edge (Chromium-based) | CVE-2021-37979 | Chromium: CVE-2021-37979 Heap buffer overflow in WebRTC | Unknown |
| Microsoft Edge (Chromium-based) | CVE-2021-37980 | Chromium: CVE-2021-37980 Inappropriate implementation in Sandbox | Unknown |
| Microsoft Edge (Chromium-based) | CVE-2021-37977 | Chromium: CVE-2021-37977 Use after free in Garbage Collection | Unknown |
| Microsoft Edge (Chromium-based) | CVE-2021-37974 | Chromium: CVE-2021-37974 Use after free in Safe Browsing | Unknown |
| Microsoft Edge (Chromium-based) | CVE-2021-37975 | Chromium: CVE-2021-37975 Use after free in V8 | Unknown |
| Microsoft Edge (Chromium-based) | CVE-2021-37976 | Chromium: CVE-2021-37976 Information leak in core | Unknown |
| Microsoft Exchange Server | CVE-2021-26427 | Microsoft Exchange Server Remote Code Execution Vulnerability | Important |
| Microsoft Exchange Server | CVE-2021-34453 | Microsoft Exchange Server Denial of Service Vulnerability | Important |
| Microsoft Exchange Server | CVE-2021-41348 | Microsoft Exchange Server Elevation of Privilege Vulnerability | Important |
| Microsoft Exchange Server | CVE-2021-41350 | Microsoft Exchange Server Spoofing Vulnerability | Important |
| Microsoft Graphics Component | CVE-2021-41340 | Windows Graphics Component Remote Code Execution Vulnerability | Important |
| Microsoft Intune | CVE-2021-41363 | Intune Management Extension Security Feature Bypass Vulnerability | Important |
| Microsoft Office Excel | CVE-2021-40473 | Microsoft Excel Remote Code Execution Vulnerability | Important |
| Microsoft Office Excel | CVE-2021-40472 | Microsoft Excel Information Disclosure Vulnerability | Important |
| Microsoft Office Excel | CVE-2021-40471 | Microsoft Excel Remote Code Execution Vulnerability | Important |
| Microsoft Office Excel | CVE-2021-40474 | Microsoft Excel Remote Code Execution Vulnerability | Important |
| Microsoft Office Excel | CVE-2021-40485 | Microsoft Excel Remote Code Execution Vulnerability | Important |
| Microsoft Office Excel | CVE-2021-40479 | Microsoft Excel Remote Code Execution Vulnerability | Important |
| Microsoft Office SharePoint | CVE-2021-40487 | Microsoft SharePoint Server Remote Code Execution Vulnerability | Important |
| Microsoft Office SharePoint | CVE-2021-40483 | Microsoft SharePoint Server Spoofing Vulnerability | Low |
| Microsoft Office SharePoint | CVE-2021-40484 | Microsoft SharePoint Server Spoofing Vulnerability | Important |
| Microsoft Office SharePoint | CVE-2021-40482 | Microsoft SharePoint Server Information Disclosure Vulnerability | Important |
| Microsoft Office SharePoint | CVE-2021-41344 | Microsoft SharePoint Server Remote Code Execution Vulnerability | Important |
| Microsoft Office Visio | CVE-2021-40480 | Microsoft Office Visio Remote Code Execution Vulnerability | Important |
| Microsoft Office Visio | CVE-2021-40481 | Microsoft Office Visio Remote Code Execution Vulnerability | Important |
| Microsoft Office Word | CVE-2021-40486 | Microsoft Word Remote Code Execution Vulnerability | Critical |
| Microsoft Windows Codecs Library | CVE-2021-40462 | Windows Media Foundation Dolby Digital Atmos Decoders Remote Code Execution Vulnerability | Important |
| Microsoft Windows Codecs Library | CVE-2021-41330 | Microsoft Windows Media Foundation Remote Code Execution Vulnerability | Important |
| Microsoft Windows Codecs Library | CVE-2021-41331 | Windows Media Audio Decoder Remote Code Execution Vulnerability | Important |
| Rich Text Edit Control | CVE-2021-40454 | Rich Text Edit Control Information Disclosure Vulnerability | Important |
| Role: DNS Server | CVE-2021-40469 | Windows DNS Server Remote Code Execution Vulnerability | Important |
| Role: Windows Active Directory Server | CVE-2021-41337 | Active Directory Security Feature Bypass Vulnerability | Important |
| Role: Windows AD FS Server | CVE-2021-40456 | Windows AD FS Security Feature Bypass Vulnerability | Important |
| Role: Windows Hyper-V | CVE-2021-40461 | Windows Hyper-V Remote Code Execution Vulnerability | Critical |
| Role: Windows Hyper-V | CVE-2021-38672 | Windows Hyper-V Remote Code Execution Vulnerability | Critical |
| System Center | CVE-2021-41352 | SCOM Information Disclosure Vulnerability | Important |
| Visual Studio | CVE-2020-1971 | OpenSSL: CVE-2020-1971 EDIPARTYNAME NULL pointer de-reference | Important |
| Visual Studio | CVE-2021-3450 | OpenSSL: CVE-2021-3450 CA certificate check bypass with X509_V_FLAG_X509_STRICT | Important |
| Visual Studio | CVE-2021-3449 | OpenSSL: CVE-2021-3449 NULL pointer deref in signature_algorithms processing | Important |
| Windows AppContainer | CVE-2021-41338 | Windows AppContainer Firewall Rules Security Feature Bypass Vulnerability | Important |
| Windows AppContainer | CVE-2021-40476 | Windows AppContainer Elevation Of Privilege Vulnerability | Important |
| Windows AppX Deployment Service | CVE-2021-41347 | Windows AppX Deployment Service Elevation of Privilege Vulnerability | Important |
| Windows Bind Filter Driver | CVE-2021-40468 | Windows Bind Filter Driver Information Disclosure Vulnerability | Important |
| Windows Cloud Files Mini Filter Driver | CVE-2021-40475 | Windows Cloud Files Mini Filter Driver Information Disclosure Vulnerability | Important |
| Windows Common Log File System Driver | CVE-2021-40443 | Windows Common Log File System Driver Elevation of Privilege Vulnerability | Important |
| Windows Common Log File System Driver | CVE-2021-40467 | Windows Common Log File System Driver Elevation of Privilege Vulnerability | Important |
| Windows Common Log File System Driver | CVE-2021-40466 | Windows Common Log File System Driver Elevation of Privilege Vulnerability | Important |
| Windows Desktop Bridge | CVE-2021-41334 | Windows Desktop Bridge Elevation of Privilege Vulnerability | Important |
| Windows DirectX | CVE-2021-40470 | DirectX Graphics Kernel Elevation of Privilege Vulnerability | Important |
| Windows Event Tracing | CVE-2021-40477 | Windows Event Tracing Elevation of Privilege Vulnerability | Important |
| Windows exFAT File System | CVE-2021-38663 | Windows exFAT File System Information Disclosure Vulnerability | Important |
| Windows Fastfat Driver | CVE-2021-41343 | Windows Fast FAT File System Driver Information Disclosure Vulnerability | Important |
| Windows Fastfat Driver | CVE-2021-38662 | Windows Fast FAT File System Driver Information Disclosure Vulnerability | Important |
| Windows Installer | CVE-2021-40455 | Windows Installer Spoofing Vulnerability | Important |
| Windows Kernel | CVE-2021-41336 | Windows Kernel Information Disclosure Vulnerability | Important |
| Windows Kernel | CVE-2021-41335 | Windows Kernel Elevation of Privilege Vulnerability | Important |
| Windows MSHTML Platform | CVE-2021-41342 | Windows MSHTML Platform Remote Code Execution Vulnerability | Important |
| Windows Nearby Sharing | CVE-2021-40464 | Windows Nearby Sharing Elevation of Privilege Vulnerability | Important |
| Windows Network Address Translation (NAT) | CVE-2021-40463 | Windows NAT Denial of Service Vulnerability | Important |
| Windows Print Spooler Components | CVE-2021-41332 | Windows Print Spooler Information Disclosure Vulnerability | Important |
| Windows Print Spooler Components | CVE-2021-36970 | Windows Print Spooler Spoofing Vulnerability | Important |
| Windows Remote Procedure Call Runtime | CVE-2021-40460 | Windows Remote Procedure Call Runtime Security Feature Bypass Vulnerability | Important |
| Windows Storage Spaces Controller | CVE-2021-40489 | Storage Spaces Controller Elevation of Privilege Vulnerability | Important |
| Windows Storage Spaces Controller | CVE-2021-41345 | Storage Spaces Controller Elevation of Privilege Vulnerability | Important |
| Windows Storage Spaces Controller | CVE-2021-26441 | Storage Spaces Controller Elevation of Privilege Vulnerability | Important |
| Windows Storage Spaces Controller | CVE-2021-40478 | Storage Spaces Controller Elevation of Privilege Vulnerability | Important |
| Windows Storage Spaces Controller | CVE-2021-40488 | Storage Spaces Controller Elevation of Privilege Vulnerability | Important |
| Windows TCP/IP | CVE-2021-36953 | Windows TCP/IP Denial of Service Vulnerability | Important |
| Windows Text Shaping | CVE-2021-40465 | Windows Text Shaping Remote Code Execution Vulnerability | Important |
| Windows Win32K | CVE-2021-40449 | Win32k Elevation of Privilege Vulnerability | Important |
| Windows Win32K | CVE-2021-41357 | Win32k Elevation of Privilege Vulnerability | Important |
| Windows Win32K | CVE-2021-40450 | Win32k Elevation of Privilege Vulnerability | Important |
Ingeniero en Ciberseguridad por la Universidad Tecnológica de Chile, Speaker, Analista de Ciberinteligencia, Investigador y Redactor para CronUp Ciberseguridad.
