CVE-2025-37910 is a vulnerability identified in the Linux kernel specifically affecting the Precision Time Protocol (PTP) implementation on Adva boards. The issue arises from a NULL pointer dereference caused by uninitialized pointers (`irig` and `dcf`) during SMA sysfs store/get operations. These operations can invoke internal functions __handle_signal_outputs() or __handle_signal_inputs(), which in turn call __handle_signal(). Because the `irig` and `dcf` pointers are not initialized on Adva boards, this leads to a NULL pointer dereference and consequently a kernel crash (denial of service). The root cause is that Adva boards do not utilize the `irig` or `dcf` functionalities, but the existing code paths still attempt to invoke these routines. The fix involves introducing Adva-specific callback functions (`ptp_ocp_sma_adva_set_outputs()` and `ptp_ocp_sma_adva_set_inputs()`) that bypass the invocation of `irig` and `dcf` related input/output routines, thereby preventing the NULL dereference and stabilizing the kernel behavior on affected hardware. This vulnerability is limited to specific Linux kernel versions identified by the commit hash ef61f5528fca6c3bbb2f8bc002fd1949c9d1f9b9 and affects systems running on Adva boards with the PTP OCP SMA driver. No known exploits are currently reported in the wild, and the vulnerability was publicly disclosed on May 20, 2025.

The primary impact of CVE-2025-37910 is a denial of service condition caused by a kernel crash due to a NULL pointer dereference. For European organizations using Linux systems on Adva hardware, particularly those relying on precise time synchronization via PTP (common in telecommunications, industrial automation, and critical infrastructure), this vulnerability could disrupt operations by causing unexpected system crashes. The loss of availability could affect network timing services, leading to degraded performance or outages in time-sensitive applications. While the vulnerability does not appear to allow privilege escalation or remote code execution, the kernel crash could be triggered locally or remotely if the sysfs interfaces are exposed or accessible, potentially allowing attackers or malfunctioning software to cause system instability. Given that Adva boards are specialized hardware often used in network infrastructure, the impact could extend to service providers and enterprises relying on these devices for synchronization and timing accuracy. The absence of known exploits reduces immediate risk, but unpatched systems remain vulnerable to accidental or intentional triggering of the crash.

To mitigate CVE-2025-37910, organizations should prioritize updating their Linux kernel to the patched version that includes the Adva-specific callback fixes. Since the vulnerability is hardware-specific, verifying whether deployed systems use Adva boards with the affected PTP OCP SMA driver is critical. Network administrators should audit sysfs permissions and restrict access to the SMA sysfs interfaces to trusted users only, minimizing the risk of unauthorized triggering. Implementing monitoring for kernel crashes and system instability can help detect attempts to exploit this vulnerability. For environments where immediate patching is not feasible, isolating affected systems from untrusted networks and limiting local user access can reduce exposure. Additionally, organizations should engage with hardware vendors and Linux distribution maintainers to ensure timely updates and confirm compatibility with patched kernels. Given the specialized nature of the hardware, coordination with infrastructure teams managing timing and synchronization services is essential to plan maintenance windows for patch deployment without disrupting critical operations.