A high-severity use-after-free and information leak vulnerability in the Linux kernel I3C master driver allows local attackers to access sensitive kernel stack data or cause system instability.

The flaw occurs due to improper management of device descriptors during the unregistration process in the I3C subsystem. A local attacker with low privileges can trigger a race condition where the kernel accesses a NULL descriptor, leading to a stack information leak or a use-after-free condition.

Successful exploitation of this vulnerability allows a local user to gain unauthorized access to kernel memory, potentially leaking sensitive information or crashing the system. Given the CVSS score of 7.8, this poses a significant risk to the integrity and availability of affected Linux systems, particularly in multi-tenant or shared environments where local access is granted to untrusted users.

Immediate Action: Update the Linux kernel to version 6.12.109, 6.18.50, 7.2.4, or later to incorporate the necessary fix for the I3C unregistration logic.

Proactive Monitoring: Monitor system logs for kernel oops or segmentation faults related to the I3C driver, which may indicate attempted exploitation.

Compensating Controls: Restrict access to the I3C subsystem devices and limit the ability of non-privileged users to interact with hardware interfaces, where applicable, to reduce the attack surface.

Public Exploit Available: Unknown

This vulnerability represents a significant security flaw within the Linux kernel that could lead to privilege escalation or system compromise. System administrators should prioritize testing and deploying the provided kernel patches across all affected environments to mitigate the risk of local exploitation.