CVE-2026-24919 is classified as a CWE-787 out-of-bounds write vulnerability found in the DFX (Design for eXcellence) module of Huawei's HarmonyOS, specifically affecting versions 4.0.0, 4.2.0, 4.3.0, and 4.3.1. An out-of-bounds write occurs when a program writes data outside the boundaries of allocated memory, which can corrupt memory, leading to unpredictable behavior such as crashes or escalation of privileges. The vulnerability requires an attacker to have local access with high privileges (PR:H) and does not require user interaction (UI:N), indicating that exploitation is limited to users or processes already with elevated permissions on the device. The attack vector is local (AV:L), meaning remote exploitation is not feasible without prior access. The impact affects integrity and availability (I:H, A:H), potentially allowing an attacker to corrupt critical data or cause denial of service by crashing the system or specific services. Confidentiality is not impacted (C:N). The vulnerability is currently not known to be exploited in the wild, and no patches have been linked yet, indicating that mitigation depends on vendor updates and internal controls. Given the nature of the DFX module, which is often involved in debugging and system diagnostics, exploitation could disrupt system stability or reliability. The CVSS 3.1 score of 6.0 reflects a medium severity, balancing the high impact on integrity and availability against the requirement for privileged local access and lack of remote exploitability.

For European organizations, the primary impact of CVE-2026-24919 lies in potential system instability or denial of service on devices running affected versions of HarmonyOS. This could disrupt business operations, especially in environments where Huawei devices are integrated into critical infrastructure, telecommunications, or enterprise mobile deployments. The integrity impact could allow malicious modification of system components or data, potentially undermining trust in device functionality. Since exploitation requires high privileges and local access, the threat is more significant in scenarios where insider threats or compromised internal systems exist. The availability impact could lead to downtime or degraded service, affecting productivity and operational continuity. Organizations relying on Huawei HarmonyOS for IoT, mobile, or embedded systems should consider the risk of cascading failures or targeted attacks exploiting this vulnerability. The absence of known exploits reduces immediate risk but does not eliminate the need for vigilance and proactive mitigation.

1. Restrict and monitor access to devices running HarmonyOS, ensuring that only trusted users have high-level privileges to reduce the risk of local exploitation. 2. Implement strict access controls and auditing on systems with Huawei devices to detect unusual activities that may indicate exploitation attempts. 3. Deploy endpoint protection solutions capable of detecting memory corruption or anomalous behavior related to out-of-bounds writes. 4. Maintain an inventory of all HarmonyOS devices and their versions to identify those affected by this vulnerability. 5. Engage with Huawei for timely updates and patches; apply security patches as soon as they become available to remediate the vulnerability. 6. For critical environments, consider network segmentation to limit the impact of compromised devices. 7. Conduct regular security training to raise awareness about the risks of privilege misuse and insider threats. 8. Monitor vendor advisories and threat intelligence feeds for any emerging exploit activity related to CVE-2026-24919.