On 13 July 2021, Microsoft released updates to address vulnerabilities in multiple products; some of the fixed flaws have been marked as currently abused. We recommend timely patching of these flaws.
- Microsoft’s July 2021 Patch Tuesday has fixed 117 vulnerabilities; including 13 classified as Critical, three actively abused flaws, and five publicly disclosed ones.
- The three vulnerabilities marked under active exploitation are:
- Microsoft stated that the details for the following vulnerabilities were made public:
- CVE-2021-34492 – a Windows Certificate Spoofing issue, CVSS:3.0 score: 8.1.
- CVE-2021-34523 – a Microsoft Exchange Server Elevation of Privilege issue, CVSS:3.0 score: 9.
- CVE-2021-33779 – a Windows ADFS Security Feature Bypass issue, CVSS:3.0 score: 8.1.
- CVE-2021-33781 – an Active Directory Security Feature Bypass, CVSS:3.0 score: 8.1.
- CVE-2021-34473 – a Microsoft Exchange Server Remote Code Execution (RCE) vulnerability that was demonstrated during Pwn2Own, a hacking competition. The CVSS:3.0 score for this flaw is 9.1 out of 10.
- Other flaws requiring attention are:
- CVE-2021-34458 – a Windows Kernel RCE impacting Windows instances hosting virtual machines with single root input/output virtualization devices. CVSS:3.0 score: 9.9.
- CVE-2021-34494 – a Windows DNS Server flaw that could allow remote code execution at a privileged service level on a listening network port without user interaction. CVSS:3.0 score: 8.8.
- CVE-2021-34514 – a Windows Kernel Elevation of Privilege Vulnerability discovered by Field Effect’s Principal Security Researcher Erik Egsgard. CVSS:3.0 score: 7.8.
- We recommend timely patching for the noted Microsoft vulnerabilities as publicly disclosed and exploited flaws make it more likely for unpatched systems to become targets of exploitation.
- In order to expedite the updates, users should go to Settings > Windows Update > Check for Updates.