Critical Patches Issued for Microsoft Products, June 8, 2021

ITS Advisory Number: 
2021-077-UPDATED
Date(s) Issued: 
Tuesday, June 8, 2021
Date Updated: 
Wednesday, June 30, 2021
Subject: 
Critical Patches Issued for Microsoft Products, June 8, 2021
Overview: 

Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for arbitrary code execution in the context of the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than those who operate with administrative user rights.

 

ORIGINAL THREAT INTELLIGENCE:

There are no reports of these vulnerabilities being exploited in the wild.

June 8 - UPDATED THREAT INTELLIGENCE:

There are six zero-day vulnerabilities that Microsoft has tracked as being actively exploited which include CVE-2021-33742, CVE-2021-33739, CVE-2021-31199, CVE-2021-31201, CVE-2021-31955 and CVE-2021-31956.

 

June 30 - UPDATED THREAT INTELLIENCE:

Researchers have proved that CVE-2021-1675 can be exploited to achieve remote code execution and proof of concept exploits have since been leaked. There are reports that the patch for CVE-2021-1675 is not enough to foil the zero-day PoC available.

 

Systems Affected: 
  • .NET Core & Visual Studio
  • 3D Viewer
  • Microsoft DWM Core Library
  • Microsoft Intune
  • Microsoft Office
  • Microsoft Office Excel
  • Microsoft Office Outlook
  • Microsoft Office SharePoint
  • Microsoft Scripting Engine
  • Microsoft Windows Codecs Library
  • Paint 3D
  • Role: Hyper-V
  • Visual Studio Code - Kubernetes Tools
  • Windows Bind Filter Driver
  • Windows Common Log File System Driver
  • Windows Cryptographic Services
  • Windows DCOM Server
  • Windows Defender
  • Windows Drivers
  • Windows Event Logging Service
  • Windows Filter Manager
  • Windows HTML Platform
  • Windows Installer
  • Windows Kerberos
  • Windows Kernel
  • Windows Kernel-Mode Drivers
  • Windows Network File System
  • Windows NTFS
  • Windows NTLM
  • Windows Print Spooler Components
  • Windows Remote Desktop
  • Windows TCP/IP
RISK
GOVERNMENT
Large and medium government entities: 
High
Small government entities: 
Medium
BUSINESS
Large and medium business entities: 
High
Small business entities: 
Medium
Home Users: 
Low
Description: 

Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for arbitrary code execution.

 

A full list of all vulnerabilities can be found at the links in the references section.

 

Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than those who operate with administrative user rights.

Actions: 
  • After appropriate testing, immediately apply patches or appropriate mitigations provided by Microsoft to vulnerable systems.
  • Run all software as a non-privileged user (one without administrative rights) to diminish the effects of a successful attack.
  • Remind all users not to visit untrusted websites or follow links provided by unknown or untrusted sources.
  • Inform and educate users regarding threats posed by hypertext links contained in emails or attachments especially from untrusted sources.
  • Apply the Principle of Least Privilege to all systems and services.

June 30 - UPDATED ACTIONS:

We recommend the following actions be taken:

  • Disable the "Print Spooler" service on machines that don't require it.