Technical Summary

The Linux kernel lockdown mode, designed to restrict access to sensitive kernel features and enforce security policies, is disabled without warning in Fedora Linux kernels version 6.12 and later. This misconfiguration allows attackers with elevated privileges to gain access to sensitive kernel internals including memory mappings, I/O ports, BPF, and kprobes. Furthermore, the vulnerability permits loading unsigned kernel modules, which can lead to execution of untrusted code and compromise Secure Boot mechanisms. The issue is specific to Fedora Linux and affects all kernel versions starting from 6.12.0 and above. The CVSS v3.1 score is 7.7, indicating a high impact on confidentiality, integrity, and availability, but requiring local privileged access and user interaction.