CVE-2026-31655

Vulnerability

Overview

A fix has been applied to the Linux kernel's pmdomain: imx8mp-blk-ctrl module. The root cause is that the NoC ADB400 port power-down handshake could cause a system hang. To prevent this, the NOC_HDCP (NOC_HDCP) clock must remain enabled at all times during the handshake process. [1]

Attack

Vector and Exploitation

This vulnerability is triggered during the power-down sequence of certain SoC blocks controlled by the i.MX8MP's block control. An attacker with the ability to manipulate power management states—potentially through a user-space interface or kernel driver interaction—could induce the hang. No authentication is explicitly required beyond local access to the system, as the hang can be triggered by normal power management operations. [2]

Impact

A successful exploitation leads to a denial of service (DoS) condition where the system becomes unresponsive (hang). Since the hangThis can be used to disrupt services or prevent the system from booting properly. The CVSS v3 base score of 5.5 (Medium) reflects moderate impact, typically requiring local access and resulting in temporary unavailability. [3]

Mitigation

The fix has been applied in the Linux kernel stable branches. Users and vendors should apply the relevant kernel patches as provided in the references to address this issue on affected i.MX8MP platforms. [4]