GFI Kerio Control Unsigned System Image Upload Root Code Execution

A remote code execution vulnerability in GFI Kerio Control 9.4.5 allows attackers with administrative access to upload and execute arbitrary code through the firmware upgrade feature. The system upgrade mechanism accepts unsigned .img files, which can be modified to include malicious scripts within the upgrade.sh or disk image components. These modified upgrade images are not validated for authenticity or integrity, and are executed by the system post-upload, enabling root access.