CVE-2025-39959: 
Linux Kernel vulnerability analysis and mitigation

CVE-2025-39959 is a vulnerability discovered in the Linux kernel's AMD ACP I2S driver, disclosed on October 9, 2025. The vulnerability specifically affects the handling of acpchipinfo members in the audio driver. This issue stems from incorrect data access methods that could lead to null pointer dereferences (NVD).

The vulnerability involves incorrect retrieval of acpchipinfo members in the AMD ACP I2S driver. The issue occurs due to the use of devgetplatdata(dev) instead of the correct method devgetdrvdata(dev->parent) for obtaining acpchipinfo members. This improper implementation was partially addressed in a previous fix for acpi2ssettdmslot but remained in other functions. The vulnerability has been assigned a CVSS v3.1 base score of 5.5 with vector string AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H, indicating a medium severity level (RedHat).

The vulnerability can potentially lead to null pointer dereferences in the Linux kernel's audio subsystem. While the impact is primarily limited to system stability rather than security breaches, it could result in system crashes or denial of service conditions when exploited (NVD).

The vulnerability has been resolved through a patch that correctly implements the retrieval of acpchipinfo members using devgetdrvdata(dev->parent). Various Linux distributions have either implemented fixes or are in the process of evaluation. Ubuntu has marked this as a medium priority issue and is currently evaluating the vulnerability across multiple releases (Ubuntu).