Number: AV21-273
Date: 9 June 2021
On 8 June 2021 Microsoft published Security Updates to address vulnerabilities in multiple products. Included were critical updates for the following:
- Windows 7, 8.1, RT 8.1 and 10
- Windows Server 2008, 2008 R2, 2012, 2012 R2, 2016 and 2019
- Windows MSHTML
- SharePoint Server
- VP9 Video Extensions
- Defender Malware Protection Engine
- SharePoint Server
Exploitation of some of these vulnerabilities could allow an actor to execute code remotely or corrupt memory.
Of note, Microsoft has stated that the following vulnerabilities are being actively exploited: CVE-2021-31955, CVE-2021-31956, CVE-2021-33739, CVE-2021-33742, CVE-2021-31199, CVE-2021-31201. These vulnerabilities could be used to disclose information or escalate privileges.
The Cyber Centre encourages users and administrators to review the provided web links and apply the necessary updates.
June 2021 Release Notes
https://msrc.microsoft.com/update-guide/releaseNote/2021-Jun
Security Update Guide
https://portal.msrc.microsoft.com/en-us/security-guidance
Note to Readers
The Canadian Centre for Cyber Security (Cyber Centre) operates as part of the Communications Security Establishment. We are Canada’s national authority on cyber security and we lead the government’s response to cyber security events. As Canada's national computer security incident response team, the Cyber Centre works in close collaboration with government departments, critical infrastructure , Canadian businesses and international partners to prepare for, respond to, mitigate, and recover from cyber events. We do this by providing authoritative advice and support, and coordinating information sharing and incident response. The Cyber Centre is outward-facing, welcoming partnerships that help build a stronger, more resilient cyber space in Canada.