Security News > 2021 > July > Update Your Windows PCs to Patch 117 New Flaws, Including 9 Zero-Days

Microsoft rolled out Patch Tuesday updates for the month of July with fixes for a total of 117 security vulnerabilities, including nine zero-day flaws, of which four are said to be under active attacks in the wild, potentially enabling an adversary to take control of affected systems.
"This Patch Tuesday comes just days after out-of-band updates were released to address PrintNightmare - the critical flaw in the Windows Print Spooler service that was found in all versions of Windows," Bharat Jogi, senior manager of vulnerability and threat research at Qualys, told The Hacker News.
"While MSFT has released updates to fix the vulnerability, users must still ensure that necessary configurations are set up correctly. Systems with misconfigurations will continue to be at risk of exploitation, even after the latest patch has been applied. PrintNightmare was a highly serious issue that further underscores the importance of marrying detection and remediation," Jogi added.
Other critical flaws remediated by Microsoft include remote code execution vulnerabilities affecting Windows DNS Server and Windows Kernel, the latter of which is rated 9.9 on the CVSS severity scale.
To install the latest security updates, Windows users can head to Start > Settings > Update & Security > Windows Update or by selecting Check for Windows updates.
Alongside Microsoft, patches have also been released by a number of other vendors to address several vulnerabilities, including -.
News URL
Related news
- Microsoft April 2025 Patch Tuesday fixes exploited zero-day, 134 flaws (source)
- Microsoft: Windows CLFS zero-day exploited by ransomware gang (source)
- Microsoft fixes actively exploited Windows CLFS zero-day (CVE-2025-29824) (source)
- PipeMagic Trojan Exploits Windows Zero-Day Vulnerability to Deploy Ransomware (source)
- Patch Tuesday: Microsoft Fixes 134 Vulnerabilities, Including 1 Zero-Day (source)
- April's Patch Tuesday leaves unlucky Windows Hello users unable to login (source)
- Emergency patch for potential SAP zero-day that could grant full system control (source)
- Microsoft pitches pay-to-patch reboot reduction subscription for Windows Server 2025 (source)
- Play Ransomware Exploited Windows CVE-2025-29824 as Zero-Day to Breach U.S. Organization (source)
- Play ransomware exploited Windows logging flaw in zero-day attacks (source)