Free unofficial patches are available for a newly identified Windows zero-day vulnerability that allows attackers to crash the Remote Access Connection Manager (RasMan) service, which operates with SYSTEM-level privileges and manages VPN and remote network connections. This denial-of-service flaw was discovered by ACROS Security while investigating a previously patched privilege escalation vulnerability (CVE-2025-59230) in RasMan. The new zero-day has not yet received a CVE ID and affects all Windows versions from Windows 7 to Windows 11, including Windows Server 2008 R2 through Server 2025. The vulnerability can be exploited by unprivileged users due to a coding error in how RasMan processes circular linked lists, leading to a crash when a null pointer is encountered. ACROS Security is providing free micropatches through its 0Patch service until Microsoft releases an official fix. Users must create an account and install the 0Patch agent to apply the micropatch automatically.