CVE-2025-55691 is a use-after-free vulnerability classified under CWE-416, affecting the Windows PrintWorkflowUserSvc service in Microsoft Windows 11 Version 24H2 (build 10.0.26100.0). Use-after-free vulnerabilities occur when a program continues to use memory after it has been freed, leading to undefined behavior such as memory corruption, crashes, or arbitrary code execution. In this case, the flaw allows an authorized local attacker with low privileges to exploit the improper memory handling in the PrintWorkflowUserSvc component to elevate their privileges. The vulnerability does not require user interaction but does require local access and has a high attack complexity, meaning exploitation is non-trivial but feasible. The CVSS v3.1 base score is 7.0, indicating a high severity with impacts on confidentiality, integrity, and availability. The vulnerability could allow attackers to execute arbitrary code with elevated privileges, potentially leading to full system compromise. No public exploits or patches are currently available, and the vulnerability was published on October 14, 2025. The PrintWorkflowUserSvc is involved in print workflow management, a critical system service, making this vulnerability particularly sensitive. Organizations using Windows 11 24H2 should be aware of this threat and prepare mitigation strategies.

If exploited, this vulnerability allows an attacker with local access to escalate privileges from a low-privileged user to higher system privileges. This can lead to unauthorized access to sensitive data, modification or deletion of critical system files, installation of persistent malware, and disruption of system availability. The compromise of PrintWorkflowUserSvc could also affect printing services and related workflows, potentially impacting business operations. Given Windows 11's widespread adoption in enterprise and government environments, successful exploitation could facilitate lateral movement within networks and enable attackers to gain control over critical systems. Although exploitation complexity is high and requires local access, the potential for full system compromise elevates the risk significantly. Organizations with remote or shared access environments are particularly vulnerable if attackers gain footholds on endpoints running the affected OS version.

1. Restrict local access to systems running Windows 11 Version 24H2, especially limiting access to trusted users only. 2. Apply the principle of least privilege to user accounts to minimize the impact of potential exploitation. 3. Monitor system and security logs for unusual activity related to the PrintWorkflowUserSvc service or privilege escalation attempts. 4. Disable or restrict the PrintWorkflowUserSvc service if printing workflows are not required or can be managed differently, reducing the attack surface. 5. Implement application control and endpoint detection and response (EDR) solutions to detect exploitation attempts. 6. Stay informed on updates from Microsoft and apply security patches immediately once available. 7. Conduct regular security audits and vulnerability assessments focusing on local privilege escalation vectors. 8. Educate users about the risks of local privilege escalation and enforce strong access controls on endpoints.