CVE-2026-24921 is a security vulnerability classified as an out-of-bounds read (CWE-125) found in the HDC (Huawei Device Connector) module of Huawei's HarmonyOS, specifically version 6.0.0. The vulnerability arises from improper bounds checking when reading memory addresses, which can cause the system to access memory outside the intended buffer. This flaw can lead to unintended information disclosure (confidentiality impact) and potentially cause system instability or crashes (availability impact). The vulnerability requires local access with high privileges (PR:H) and user interaction (UI:R) to be exploited, limiting remote exploitation possibilities. The CVSS v3.1 base score is 4.8, indicating medium severity, with the vector emphasizing local attack vector, low attack complexity, and partial confidentiality loss but no integrity impact. No public exploits or patches are currently available, and the vulnerability was reserved and published in early 2026. The HDC module is critical for device communication and management within HarmonyOS, so exploitation could disrupt device operations and leak sensitive data. Given the nature of the vulnerability, attackers would need to have significant access and user cooperation to exploit it successfully.

For European organizations, the impact of CVE-2026-24921 depends largely on the extent of HarmonyOS device deployment within their infrastructure. Organizations using Huawei devices running HarmonyOS 6.0.0 could face availability issues if the vulnerability is exploited, potentially causing device crashes or service interruptions. Confidentiality risks, while limited, could expose sensitive information stored or processed by the affected module. Sectors such as telecommunications, critical infrastructure, and enterprises with Huawei-based IoT or mobile devices are at higher risk. Disruption in device availability could affect operational continuity, especially in environments relying on Huawei technology for communication or control. The requirement for local privileged access and user interaction reduces the likelihood of widespread attacks but does not eliminate insider threat or targeted attack risks. The absence of known exploits currently lowers immediate risk but underscores the need for vigilance as exploit development could follow publication.

1. Limit local privileged access to HarmonyOS devices, enforcing strict access controls and monitoring for unauthorized privilege escalations. 2. Educate users about the risks of interacting with untrusted applications or prompts that could facilitate exploitation. 3. Implement robust endpoint detection and response (EDR) solutions to identify anomalous behavior indicative of exploitation attempts. 4. Regularly audit device configurations and installed software to ensure compliance with security policies. 5. Coordinate with Huawei for timely patch deployment once available, and prioritize updates on critical devices. 6. Employ network segmentation to isolate vulnerable devices and reduce potential lateral movement in case of compromise. 7. Maintain comprehensive logging and incident response plans tailored to HarmonyOS environments. 8. Consider alternative device platforms or additional security layers if Huawei device usage is extensive and risk tolerance is low.