CVE-2025-55331 is a use-after-free vulnerability classified under CWE-416, discovered in the Windows PrintWorkflowUserSvc component of Microsoft Windows 11 Version 25H2 (build 10.0.26200.0). This vulnerability arises when the service improperly manages memory, freeing an object while it is still in use, which can lead to memory corruption. An attacker with authorized local access but low privileges can exploit this flaw to execute arbitrary code with elevated privileges, effectively escalating their rights on the system. The vulnerability does not require user interaction, increasing its risk profile in environments where local access is possible. The CVSS v3.1 score of 7.0 indicates high severity, with impacts on confidentiality, integrity, and availability (all rated high). The attack complexity is high, requiring local access and some conditions to be met, but no user interaction is needed. Currently, there are no known exploits in the wild, and no patches have been published yet, though the vulnerability has been officially reserved and published in the CVE database. The flaw specifically targets the PrintWorkflowUserSvc, a service involved in managing print workflows, which is commonly enabled in enterprise environments. Exploitation could allow attackers to bypass security controls and gain administrative privileges, posing a significant threat to system security and stability.

For European organizations, this vulnerability presents a significant risk, particularly in sectors relying heavily on Windows 11 25H2 deployments such as finance, healthcare, government, and critical infrastructure. Successful exploitation could lead to privilege escalation, enabling attackers to execute malicious code with system-level rights, potentially leading to data breaches, ransomware deployment, or disruption of critical services. The impact on confidentiality, integrity, and availability is high, as attackers could manipulate or exfiltrate sensitive data, alter system configurations, or cause denial of service. Given the local access requirement, the threat is more pronounced in environments with many users or where endpoint security is weak. Organizations with extensive print infrastructure or automated print workflows may be more exposed. The lack of current exploits provides a window for proactive mitigation, but the high severity necessitates urgent attention to patching and access control.

1. Monitor Microsoft security advisories closely and apply patches immediately once released to address CVE-2025-55331. 2. Restrict local access to systems running Windows 11 Version 25H2, especially limiting access to trusted users only. 3. Implement strict least privilege policies to minimize the number of users with local access rights. 4. Disable or restrict the PrintWorkflowUserSvc service where printing workflows are not essential or can be temporarily suspended. 5. Employ endpoint detection and response (EDR) solutions to monitor for anomalous behavior related to PrintWorkflowUserSvc or privilege escalation attempts. 6. Conduct regular audits of local user accounts and permissions to ensure no unauthorized privilege assignments. 7. Educate IT staff and users about the risks of local privilege escalation vulnerabilities and the importance of reporting suspicious activity. 8. Use application whitelisting and code integrity policies to prevent unauthorized code execution. 9. In high-security environments, consider network segmentation to isolate critical systems and reduce the risk of lateral movement following exploitation.