CVE-2023-52882 is a vulnerability identified in the Linux kernel specifically related to the clock management subsystem for the sunxi-ng platform, particularly the H6 SoC (System on Chip). The issue arises during the phase where the PLL (Phase-Locked Loop) CPUX clock rate is changed while the CPU is actively running from this clock source. Under normal circumstances, changing the PLL CPUX clock rate dynamically is supported and functions correctly in the majority of cases. However, sporadically, this operation causes system instability, which manifests as system crashes or other undefined behaviors. The root cause is linked to the lack of proper reparenting of the CPUX clock during the PLL CPUX rate change. Reparenting here refers to switching the clock source to a more stable clock (such as a 24 MHz oscillator) during frequency transitions to avoid instability. The vulnerability was discovered after extensive testing involving over 30 hours of frequency switching, which revealed that without this reparenting, instability issues could occur. The fix involves ensuring that the CPUX clock is reparented to a stable clock source during PLL CPUX rate changes, thereby eliminating the instability. This vulnerability affects specific Linux kernel versions identified by the commit hash 524353ea480b0094c16f2b5684ce7e0a23ab3685. There are no known exploits in the wild at the time of publication, and no CVSS score has been assigned yet. The vulnerability primarily impacts systems running Linux on sunxi-ng H6 hardware platforms, which are commonly found in embedded devices and certain ARM-based single-board computers.

For European organizations, the impact of CVE-2023-52882 depends largely on the deployment of affected hardware and Linux kernel versions. Organizations using embedded systems, IoT devices, or ARM-based single-board computers with the sunxi-ng H6 SoC running vulnerable Linux kernels may experience system crashes or unpredictable behavior. This can lead to service interruptions, reduced reliability of critical systems, and potential data loss if systems reboot unexpectedly. In industrial, manufacturing, or telecommunications sectors where embedded Linux devices are prevalent, such instability could disrupt operational technology environments. Although the vulnerability does not directly expose confidentiality or integrity risks, the availability and reliability of affected systems are at risk. For enterprises relying on these devices for automation, monitoring, or control, the instability could translate into operational downtime and increased maintenance costs. Since no known exploits exist, the immediate threat level is moderate, but unpatched systems remain vulnerable to accidental crashes or potential future exploitation if attackers find ways to trigger the instability deliberately.

To mitigate CVE-2023-52882, European organizations should: 1) Identify all devices running the affected Linux kernel versions on sunxi-ng H6 platforms within their infrastructure. 2) Apply the official Linux kernel patch that implements the reparenting of the CPUX clock to a stable oscillator during PLL CPUX rate changes. This patch is referenced by the commit hash 524353ea480b0094c16f2b5684ce7e0a23ab3685 and should be integrated into the kernel builds used by the organization. 3) For embedded devices where kernel updates are challenging, consider firmware updates or vendor-provided patches that incorporate this fix. 4) Implement monitoring for system stability and logs to detect unexpected crashes or frequency switching anomalies. 5) Engage with hardware and software vendors to ensure timely updates and support for affected devices. 6) Where possible, isolate critical embedded systems from external networks to reduce the risk of remote exploitation attempts. 7) Conduct thorough testing of updated kernels in staging environments before deployment to avoid regressions.