CVE-2024-40991 addresses a vulnerability in the Linux kernel specifically within the dmaengine subsystem, in the ti: k3-udma-glue driver component. The issue lies in the helper function of_k3_udma_glue_parse_chn_by_id(), which incorrectly calls of_node_put() on the udmax_np device node without having previously incremented its reference count. In Linux device tree handling, proper reference counting is critical to ensure that device nodes are not prematurely released or double-freed, which can lead to use-after-free conditions or memory corruption. The erroneous invocation of of_node_put() without a corresponding of_node_get() increment can cause the reference count to drop below zero, potentially leading to kernel instability or crashes. Although this vulnerability does not appear to have known exploits in the wild, the underlying flaw could be leveraged by an attacker with local access or through crafted device tree data to cause denial of service or potentially escalate privileges by corrupting kernel memory. The fix involves correcting the reference counting logic to ensure that of_node_put() is only called after a proper increment, preserving kernel memory integrity. This vulnerability affects specific versions of the Linux kernel identified by the commit hash 81a1f90f20af71728f900f245aa69e9425fdef84, indicating it is a recent issue resolved shortly after discovery. Since the vulnerability is in a kernel driver related to DMA engine glue code for TI K3 platforms, it primarily impacts embedded or specialized systems using these TI SoCs running Linux kernels with this code path.

For European organizations, the impact of CVE-2024-40991 depends largely on their use of affected TI K3 SoC-based embedded systems running Linux kernels with the vulnerable driver. Such systems are common in industrial control, telecommunications infrastructure, and specialized networking equipment. A successful exploitation could lead to kernel crashes causing denial of service, disrupting critical operations. In worst cases, memory corruption could be leveraged for privilege escalation, threatening system integrity and confidentiality. This is particularly concerning for sectors such as manufacturing, energy, and telecom providers in Europe that rely on embedded Linux devices for operational technology (OT) and network functions. While no public exploits are known, the vulnerability’s presence in kernel code means that any unpatched systems remain at risk. The potential for disruption in critical infrastructure or industrial environments could have cascading effects on service availability and data security within European enterprises.

European organizations should prioritize patching Linux kernels to versions that include the fix for CVE-2024-40991, especially on devices using TI K3 SoCs or related embedded platforms. Since the vulnerability arises from improper reference counting in kernel device tree handling, updating to the latest stable kernel releases or vendor-provided patches is essential. For embedded devices where kernel upgrades are challenging, organizations should work with hardware vendors to obtain patched firmware or kernel images. Additionally, organizations should audit their device inventories to identify systems running affected kernel versions and TI K3 hardware. Employing kernel hardening techniques such as Kernel Address Space Layout Randomization (KASLR), and enabling kernel lockdown modes can reduce exploitation risk. Monitoring system logs for kernel errors or crashes related to dmaengine or device tree parsing can help detect exploitation attempts. Network segmentation and strict access controls limiting local access to embedded devices will also mitigate attack vectors requiring local presence.