Windows PowerShell 0-Day Remote Code Execution Vulnerability (CVE-2025-54100)

Microsoft has disclosed a critical 0-day vulnerability in Windows PowerShell, tracked as CVE-2025-54100, which allows attackers to execute arbitrary code on affected systems. The flaw arises from improper neutralization of special elements in PowerShell's command processing, enabling command injection if an attacker can trick a user into running a malicious script or command. Exploitation requires local access and user interaction, but successful attacks can result in privilege escalation and full system compromise, making this vulnerability a significant risk for organizations relying on PowerShell for administration and automation.

No official patch is available yet, and Microsoft has urged organizations to apply immediate mitigations and monitor for updates. The vulnerability is rated as 'Important' with a CVSS score of 7.8, and its potential for chaining with other exploits increases its attractiveness to threat actors. Attack vectors include phishing, watering-hole attacks, and supply-chain compromises where PowerShell scripts are abused during software installation or updates. Security teams are advised to remain vigilant and implement recommended mitigations until a patch is released.