CVE-2025-49148 is a high-severity vulnerability affecting thevindu-w's ClipShare Server for Windows versions prior to 3.8.5. ClipShare is a lightweight, cross-platform clipboard sharing tool. The vulnerability arises from an uncontrolled search path element (CWE-427) due to the server's use of the default Windows DLL search order. Specifically, the ClipShare Server loads critical system DLLs such as CRYPTBASE.dll and WindowsCodecs.dll from its own executable directory before the system path. This behavior allows a local, non-privileged user who has write access to the folder containing clip_share.exe to place malicious DLLs with the same names as these system libraries. When the ClipShare Server loads these malicious DLLs, it executes arbitrary code within the server's context. If the server process is running with elevated privileges (e.g., launched by an Administrator), this leads to a reliable local privilege escalation. The vulnerability requires local access with write permissions to the executable directory and some user interaction (server restart or reload) to trigger the exploit. The issue is resolved in version 3.8.5 of ClipShare Server by presumably changing the DLL loading order or hardening the search path. No known exploits are currently reported in the wild. The CVSS v3.1 base score is 7.3, reflecting high impact on confidentiality, integrity, and availability, with low attack complexity but requiring local privileges and user interaction.

For European organizations, this vulnerability poses a significant risk especially in environments where ClipShare Server is deployed on Windows systems. An attacker with local access and write permissions to the ClipShare installation directory can execute arbitrary code and escalate privileges to administrator level. This could lead to full system compromise, data theft, unauthorized access to sensitive information, and disruption of clipboard sharing services. In corporate or government environments where clipboard sharing tools are used for productivity, this vulnerability could be leveraged to move laterally within networks or establish persistence. The high impact on confidentiality, integrity, and availability means that critical business operations could be affected. Additionally, if ClipShare Server is running on systems with sensitive data or connected to critical infrastructure, the consequences could be severe. The requirement for local access limits remote exploitation but insider threats or compromised user accounts could exploit this vulnerability.

European organizations should immediately upgrade all instances of ClipShare Server to version 3.8.5 or later, where the vulnerability is fixed. Until upgrades are complete, restrict write permissions to the ClipShare installation directory to trusted administrators only, preventing non-privileged users from placing malicious DLLs. Implement application whitelisting or code integrity policies to block unauthorized DLLs from loading. Monitor file system changes in the ClipShare directory for suspicious activity. Additionally, run ClipShare Server with the least privileges necessary and avoid running it under administrator accounts. Employ endpoint detection and response (EDR) solutions to detect anomalous DLL loading or privilege escalation attempts. Conduct user awareness training to reduce the risk of local user exploitation. Finally, review and harden local access controls and audit logs to detect and respond to potential exploitation attempts promptly.