CVE-2025-55331 is a use-after-free vulnerability classified under CWE-416 found in the Windows PrintWorkflowUserSvc service of Microsoft Windows 11 Version 25H2 (build 10.0.26200.0). The flaw arises when the service improperly manages memory, allowing an attacker with authorized local access and low privileges to exploit the use-after-free condition to execute arbitrary code with elevated privileges. This elevation of privilege (EoP) can enable the attacker to gain SYSTEM-level access, compromising the confidentiality, integrity, and availability of the system. The vulnerability does not require user interaction but does require the attacker to have some level of local access, which limits remote exploitation. The CVSS v3.1 base score is 7.0, reflecting high severity due to the potential for complete system compromise, though the attack complexity is high and privileges are required. No public exploits or patches are currently available, indicating the need for vigilance and proactive mitigation. The vulnerability affects a core Windows service related to print workflows, which is commonly present on Windows 11 systems, making it a significant risk for environments running this OS version.

For European organizations, this vulnerability poses a significant risk as it allows local attackers to escalate privileges and potentially gain full control over affected Windows 11 systems. This could lead to unauthorized access to sensitive data, disruption of critical services, and deployment of malware or ransomware. Organizations with large deployments of Windows 11 25H2, especially in sectors like finance, healthcare, government, and critical infrastructure, could face severe operational and reputational damage. The requirement for local access somewhat limits remote exploitation but insider threats or compromised endpoints could be leveraged to exploit this vulnerability. The impact on confidentiality, integrity, and availability is high, making it a critical concern for enterprise security teams. Additionally, the lack of known exploits currently provides a window for mitigation before active exploitation begins.

1. Implement strict local user access controls to limit the number of users with local login privileges, especially on critical systems. 2. Monitor and audit usage of the PrintWorkflowUserSvc service and related print workflow activities for unusual or unauthorized behavior. 3. Employ application whitelisting and endpoint detection and response (EDR) solutions to detect attempts to exploit use-after-free conditions or privilege escalation. 4. Once available, apply Microsoft security updates and patches for Windows 11 Version 25H2 immediately. 5. Use least privilege principles to restrict user permissions and avoid running unnecessary services with elevated privileges. 6. Educate IT staff and users about the risks of local privilege escalation and enforce strong endpoint security policies. 7. Consider network segmentation to isolate critical systems and reduce the risk of lateral movement following local compromise.