Microsoft’s latest Patch Tuesday resolves 63 vulnerabilities across Windows and related components. The release includes an actively exploited zero‑day in the Windows kernel (CVE‑2025‑62215), four issues rated critical, and dozens of high‑severity bugs affecting privilege escalation, remote code execution (RCE), information disclosure, and security feature bypass. Organizations should prioritize deployment on exposed endpoints and servers to disrupt common post‑exploitation playbooks observed by Microsoft Security Response Center (MSRC) and Microsoft Threat Intelligence (MSTIC).
Zero‑day CVE‑2025‑62215: Windows kernel race condition enabling SYSTEM
CVE‑2025‑62215 (CVSS 7.0) is exploited in the wild. According to Microsoft, the flaw is a race condition in the Windows kernel that can lead to a double free—freeing the same memory twice—resulting in kernel heap corruption. An attacker with low‑privileged local access can win the race on a shared kernel resource and overtake control flow, enabling privilege escalation to SYSTEM. This bug is primarily a post‑exploitation enabler: threat actors often secure initial access via phishing, social engineering, or a separate vulnerability, then escalate privileges to persist, disable defenses, and move laterally.
Critical RCE in graphics stack and WSLg
CVE‑2025‑60724 (CVSS 9.8): Graphics component RCE
Microsoft addressed a heap buffer overflow in a graphics component that allows remote code execution with the current user’s privileges. While specifics are limited, exploitation paths in graphics pipelines have historically included crafted files or content that trigger vulnerable parsing code. Systems heavily using graphics‑intensive applications, VDI, and endpoints processing untrusted media are at elevated risk.
CVE‑2025‑62220 (CVSS 8.8): WSLg RCE
A second RCE affects the Windows Subsystem for Linux GUI (WSLg). Successful exploitation can execute arbitrary code under the user context. Because WSLg is prevalent on developer and engineering workstations, compromise here may provide a springboard to sensitive source code, build systems, or cloud credentials—amplifying the blast radius of a single endpoint intrusion.
Kerberos “CheckSum” (CVE‑2025‑60704): weakened authentication and MITM
CVE‑2025‑60704 (dubbed CheckSum by Silverfort; CVSS 7.5) stems from a missing cryptographic verification step in Windows Kerberosman‑in‑the‑middle scenarios and user impersonation. In Active Directory environments, attacks on Kerberos authentication can rapidly escalate into domain‑wide resource compromise, making prompt remediation essential for enterprise defenders.
Release statistics and attack trends
Out of 63 CVEs, 4 are critical and 59 are important. The distribution underscores current attacker priorities: 29 privilege escalation issues, 16 RCE, and 11 information disclosure, with the rest covering DoS, security feature bypass, and spoofing. This pattern aligns with real‑world incidents where adversaries chain initial access with privilege escalation and lateral movement to achieve objectives such as data theft or ransomware deployment.
Windows 10 ESU and out‑of‑band fix
Microsoft also shipped the first wave of Extended Security Updates (ESU) for Windows 10 following the end of mainstream support. Some customers reported registration issues when enrolling in ESU; Microsoft released an out‑of‑band update to correct enrollment problems and restore access to the extended servicing channel.
Patch prioritization and defensive actions
Prioritize deployment for CVE‑2025‑62215, CVE‑2025‑60724, CVE‑2025‑62220, and CVE‑2025‑60704, focusing first on high‑exposure systems such as developer workstations, terminal servers, VDI hosts, and endpoints that actively use graphics workloads or WSLg. Enhance monitoring for abnormal privilege escalation attempts and Kerberos anomalies, and verify that EDR sensors, application control policies, and tamper‑protection settings remain enforced post‑patch.
To reduce operational risk, schedule a maintenance window, test critical business applications in staging, and enable built‑in Windows mitigations where feasible (e.g., attack surface reduction rules and strong credential hygiene). This Patch Tuesday reinforces a durable trend: adversaries blend social engineering or initial access bugs with local escalation to SYSTEM and lateral movement. Rapid patching, risk‑based prioritization, and vigilant authentication monitoring remain the most effective measures to prevent compromise and contain intrusion attempts.
