CVE-2025-55685 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). This vulnerability arises when the service improperly manages memory, leading to a condition where freed memory is accessed again, potentially allowing an attacker to execute arbitrary code or corrupt memory. The flaw requires an attacker to have authorized local access with low privileges but does not require user interaction, making it a potent vector for privilege escalation. Exploiting this vulnerability could allow an attacker to elevate their privileges from a low-privileged user to SYSTEM or equivalent, compromising the confidentiality, integrity, and availability of the affected system. The CVSS v3.1 base score is 7.0, indicating high severity, with an attack vector limited to local access (AV:L), high attack complexity (AC:H), and requiring low privileges (PR:L). No known exploits are currently in the wild, and no patches have been released yet, increasing the risk window. The vulnerability is particularly concerning for environments where local user accounts have some access, such as shared workstations or terminal servers. The PrintWorkflowUserSvc is involved in print job processing workflows, a common feature in enterprise environments, increasing the potential attack surface. The vulnerability was reserved in August 2025 and published in October 2025, indicating recent discovery and disclosure.

For European organizations, this vulnerability poses a significant risk due to the widespread adoption of Windows 11 25H2 in enterprise and government environments. Successful exploitation could lead to unauthorized privilege escalation, enabling attackers to execute arbitrary code with SYSTEM-level privileges. This could result in data breaches, disruption of critical services, and lateral movement within networks. Confidentiality is at risk as attackers could access sensitive information; integrity is compromised through potential unauthorized changes to system files or configurations; and availability could be affected if attackers disable or disrupt printing services or other critical system components. The requirement for local access limits remote exploitation but does not eliminate risk in environments with multiple users or where attackers have gained initial footholds. The lack of a patch increases exposure time, and the absence of known exploits suggests a window for proactive defense. Organizations involved in critical infrastructure, finance, healthcare, and government sectors are particularly vulnerable due to the potential impact on sensitive data and services.

1. Enforce strict local user account management, limiting the number of users with local access and ensuring least privilege principles are applied. 2. Monitor and audit local privilege escalation attempts and unusual behavior related to the PrintWorkflowUserSvc service. 3. Disable or restrict the PrintWorkflowUserSvc service where printing workflows are not required or can be managed differently. 4. Implement application whitelisting and endpoint detection and response (EDR) solutions to detect exploitation attempts targeting use-after-free conditions. 5. Prepare for rapid deployment of patches once Microsoft releases updates by maintaining an up-to-date asset inventory and patch management process. 6. Educate users and administrators about the risks of local privilege escalation vulnerabilities and the importance of reporting suspicious activity. 7. Consider network segmentation to limit the impact of compromised local accounts and reduce lateral movement opportunities. 8. Use enhanced logging and alerting on Windows Event Logs related to printing services and privilege escalations.