Security News > 2021 > June > Microsoft June 2021 Patch Tuesday fixes 6 exploited zero-days, 50 flaws
Today is Microsoft's June 2021 Patch Tuesday, and with it comes fixes for seven zero-day vulnerabilities and a total of 50 flaws, so Windows admins will be scrambling to get devices secured.
Microsoft has fixed 50 vulnerabilities with today's update, with five classified as Critical and forty-five as Important.
As part of today's Patch Tuesday, Microsoft has fixed seven zero-day vulnerabilities, with six of them known to be exploited in the past.
In a report released today by Kaspersky, researchers explain that the CVE-2021-31955 and CVE-2021-31956 zero-day vulnerabilities were used in attacks by a new threat actor group known as PuzzleMaker.
The threat actors then chained together the CVE-2021-31955 and CVE-2021-31956 vulnerabilities to elevate their privileges on the compromised Windows device.
Below is the full list of resolved vulnerabilities and released advisories in the June 2021 Patch Tuesday updates.
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Related Vulnerability
| DATE | CVE | VULNERABILITY TITLE | RISK |
|---|---|---|---|
| 2021-06-08 | CVE-2021-31956 | Integer Underflow (Wrap or Wraparound) vulnerability in Microsoft products Windows NTFS Elevation of Privilege Vulnerability | 0.0 |
| 2021-06-08 | CVE-2021-31955 | Unspecified vulnerability in Microsoft products Windows Kernel Information Disclosure Vulnerability | 0.0 |