Microsoft July 2021 Patch Tuesday fixes 9 zero-days, 117 flaws

Today is Microsoft's July 2021 Patch Tuesday, and with it comes fixes for nine zero-day vulnerabilities and a total of 117 flaws, so Windows admins will be pulling their hair out as they scramble to get devices patched and secured.

Microsoft has fixed 117 vulnerabilities with today's update, with 13 classified as Critical, 1 Moderate, and 103 as Important.

Of the 117 vulnerabilities, 44 are remote code execution, 32 are for elevation of privilege, 14 are information disclosure, 12 are Denial of Service, 8 are security feature bypass, and seven are spoofing vulnerabilities.

July's Patch Tuesday includes nine zero-day vulnerabilities, with four actively exploited in the wild.

Microsoft classifies a zero-day vulnerability as publicly disclosed or actively exploited with no official security updates or released.

There was one publicly disclosed and actively exploited vulnerability known as PrintNightmare.

Finally, there are three actively exploited Windows vulnerabilities that were not publicly disclosed.

Last month, a proof-of-concept exploit was released by accident for the zero-day PrintNightmare vulnerability that allows remote code execution and local privilege escalation.

Microsoft's OOB patch only resolves the vulnerability if the Point and Print policy is disabled. The patch can be bypassed for those devices that still have this registry setting enabled to achieve remote code execution and local privilege escalation.

However, Microsoft states that the patches are working as intended and that Windows admins should install the patches immediately as the vulnerabilities are being actively exploited.

"Our investigation has shown that the OOB security update is working as designed and is effective against the known printer spooling exploits and other public reports collectively being referred to as PrintNightmare," the Microsoft Security Response Center explains.

"All reports we have investigated have relied on the changing of default registry setting related to Point and Print to an insecure configuration."

Security research and Mimikatz creator feels that the patch still needs improvement to protect against the bypasses he and others have found

Below is the full list of resolved vulnerabilities and released advisories in the July 2021 Patch Tuesday updates. To access the full description of each vulnerability and the systems that it affects, you can view the full report here.