CVE-2023-52985 is a vulnerability identified in the Linux kernel specifically affecting the ARM64 architecture with the imx8mm-verdin device tree source (DTS) configuration. The issue arises when the system enters suspend states such as freeze or memory suspend. During these suspend operations, the Fast Ethernet Controller (fec) driver attempts to power down the Ethernet physical layer device (phy). However, the phy subsystem currently lacks the functionality to properly power down the phy, which leads to a kernel crash and results in a non-responsive system. The kernel crash is evidenced by a call trace involving phy_error, kszphy_handle_interrupt, phy_interrupt, irq_thread_fn, irq_thread, kthread, and ret_from_fork functions. The root cause is the fec driver's attempt to power down the phy during suspend, which is unsupported and causes instability. The resolution implemented disables the feature of powering down the Ethernet phy to prevent the kernel crash. This fix ensures that during suspend states, the phy remains powered, avoiding the problematic state transition that causes the kernel panic. The vulnerability affects Linux kernel versions identified by the commit hash 6a57f224f7346c8d23596f2ef1ce360669926f54 and is currently published without a CVSS score or known exploits in the wild. The vulnerability is specific to the ARM64 platform with the imx8mm-verdin DTS configuration, which is used in certain embedded systems and IoT devices based on NXP's i.MX8M Mini processors.

For European organizations, the impact of CVE-2023-52985 is primarily on embedded systems and devices running Linux on ARM64 platforms with the imx8mm-verdin configuration. These devices are often used in industrial automation, IoT deployments, and specialized networking equipment. A kernel crash during suspend operations can lead to system instability, unexpected reboots, or denial of service conditions. This can disrupt critical infrastructure operations, manufacturing processes, or network availability. Although this vulnerability does not directly lead to remote code execution or data breach, the resulting denial of service can impact operational continuity and reliability. Organizations relying on affected hardware for edge computing, industrial control systems, or network appliances may experience outages or degraded performance. The lack of known exploits reduces immediate risk, but unpatched systems remain vulnerable to crashes triggered by suspend operations, which could be exploited by local attackers or malicious insiders to disrupt services. The impact is more pronounced in environments where devices frequently enter suspend states to conserve power or where uptime is critical.

To mitigate CVE-2023-52985, European organizations should: 1) Apply the latest Linux kernel patches that disable the Ethernet phy power-down feature for the affected imx8mm-verdin DTS configuration. This prevents the kernel crash by avoiding unsupported phy power state transitions. 2) Identify and inventory all devices running the affected Linux kernel versions on ARM64 platforms with the imx8mm-verdin configuration, prioritizing those used in critical infrastructure or production environments. 3) Where patching is not immediately possible, consider disabling suspend states (freeze or memory suspend) on affected devices to prevent triggering the vulnerability. 4) Monitor system logs for kernel crash traces related to phy_error or fec driver issues to detect attempts to exploit or trigger the vulnerability. 5) Engage with hardware and software vendors to confirm the availability of updated firmware or kernel versions that address this issue. 6) Implement robust backup and recovery procedures to minimize downtime in case of kernel crashes. 7) For new deployments, prefer hardware and kernel versions that have this vulnerability resolved to avoid exposure.