CVE-2025-22009 is a vulnerability identified in the Linux kernel related to the regulator subsystem, specifically involving the 'dummy' regulator driver. The issue arises during the boot process where a NULL pointer dereference can occur in the function kobject_get(). The root cause is a race condition between the probing of the 'dummy' regulator driver and the anatop regulator driver, which are executed by different kernel worker threads concurrently. This asynchronous probing leads to a situation where the 'dummy_regulator_rdev' pointer remains NULL when accessed, causing the kernel to dereference a NULL pointer and potentially crash or cause instability during system startup. The vulnerability is tied to the regulator framework's handling of device registration and supply resolution, where synchronization between these probe routines is lacking. The reporter notes that forcing synchronous probing of the 'dummy' regulator could mitigate the issue with minimal boot time impact. No known exploits are currently reported in the wild, and no CVSS score has been assigned yet. The vulnerability affects specific Linux kernel versions identified by commit hashes, indicating it is a recent and targeted fix in the kernel source code.

For European organizations, this vulnerability could lead to system instability or denial of service (DoS) during the boot process on affected Linux systems. Since Linux is widely used in servers, embedded devices, and critical infrastructure across Europe, systems running vulnerable kernel versions may experience unexpected reboots or failures, impacting availability. This is particularly critical for environments requiring high uptime such as financial institutions, telecommunications, healthcare, and industrial control systems. While the vulnerability does not directly expose confidentiality or integrity risks, the availability impact could disrupt business operations and services. The lack of known exploits reduces immediate risk, but the potential for DoS in critical systems makes timely patching important. Organizations relying on custom or older Linux kernels should verify if their versions are affected and plan updates accordingly.

1. Apply the official Linux kernel patches that address this issue as soon as they become available. Monitor kernel mailing lists and vendor advisories for updates. 2. For organizations using custom or embedded Linux distributions, coordinate with vendors or maintainers to integrate the fix promptly. 3. Implement boot-time monitoring and logging to detect kernel crashes or anomalies related to regulator probing. 4. Consider configuring kernel boot parameters or systemd services to enable automatic recovery or reboot in case of boot failures. 5. Test kernel updates in staging environments to ensure compatibility and stability before deployment in production. 6. If immediate patching is not feasible, evaluate the possibility of forcing synchronous probing of the 'dummy' regulator driver as a temporary workaround, understanding the potential boot time impact. 7. Maintain robust backup and recovery procedures to minimize downtime in case of system failures triggered by this vulnerability.