A high-severity use-after-free vulnerability in the Linux kernel RDMA core could allow a local authenticated attacker to compromise system integrity or cause a denial of service.

The vulnerability exists in the RDMA core subsystem, specifically within the ib_dealloc_pd_user function. An attacker with local low-privileged access can trigger a race condition because the restrack object is not removed before internal resources are freed, leading to a use-after-free condition.

Successful exploitation of this flaw could allow a local user to escalate privileges, cause kernel panics resulting in system downtime, or access sensitive memory locations. Given the CVSS score of 7.8, this represents a significant risk to the availability and integrity of systems running affected Linux kernels, particularly in multi-tenant or shared-hosting environments where untrusted users possess local access.

Immediate Action: Update your Linux kernel to version 6.1.188, 6.6.157, 6.12.110, 6.18.52, or any subsequent stable release provided by your distribution vendor.

Proactive Monitoring: Monitor system logs for kernel oops or segmentation faults, which may indicate attempted exploitation or unexpected instability in the RDMA subsystem.

Compensating Controls: If immediate patching is not possible, restrict local user access to the system and limit the usage of RDMA-capable hardware interfaces to authorized users only.

Public Exploit Available: Unknown

Organizations should prioritize the deployment of these kernel updates as part of their regular patch management cycle. Because this vulnerability affects the core kernel, it is critical to test the patches in a staging environment to ensure compatibility with existing hardware and RDMA configurations before deploying to production systems.