Windows PowerShell 0-Day Vulnerability Let Attackers Execute Malicious Code

**Executive summary:** Microsoft disclosed CVE-2025-54100, a Windows PowerShell vulnerability (CVSS 7.8) that allows attackers to execute arbitrary code via improper neutralization of special elements (CWE-77); the flaw affects many Windows desktop and server versions and has been addressed through multiple KB updates and recommended mitigations, though exploitation requires local access and user interaction.