Microsoft Released September 2025 Software Updates
Microsoft September 2025 patches fix 81 flaws including 2 publicly disclosed zero-day vulnerabilities
Microsoft has released software updates as part of its September 2025 Patch Tuesday. The updates fix 81 security vulnerabilities in total, including 2 zero-day vulnerabilities.
The breakdown of the vulnerabilities are as follows:
-
41 privilege escalation
-
2 security feature bypass
-
22 remote code execution
-
16 information disclosure
-
3 denial of service
-
1 spoofing
The actively exploited vulnerabilities are as follows:
-
CVE-2025-55234vulnerability in Windows SMB that allows elevation of privilege -
CVE-2024-21907vulnerability in Newtonsoft.Json library that allows denial of service
Why You Should Care?
Zero-day vulnerabilities are vulnerabilities where a flaw has been identified but there was no fix for the flaw, which means attackers will try to exploit as many targets as possible before users fix the vulnerability. This makes it extra dangerous, and needs to be addressed as soon as possible.
In this case, two zero-day vulnerabilities are publicly disclosed, which means attackers have the information to build an exploit. It is only a matter of time before the attackers compromise your business. Now that patches are available, it is critical to apply the patches as soon as possible to avoid getting compromised.
What Should You Do?
-
Test the patches ASAP at your organization, and make sure it does not break any business applications
-
Prioritize patching the publicly disclosed zero-days
-
Roll out the rest of the Patch Tuesday updates