CVE-2025-31171 is a security vulnerability identified in Huawei's HarmonyOS version 5.0.0, specifically within the kernel file system module. The vulnerability is classified under CWE-862, which corresponds to Missing Authorization. This means that the system fails to properly enforce access control checks before allowing certain operations. In this case, the flaw allows an attacker to bypass file read permissions, enabling unauthorized access to files that should be protected. The vulnerability does not require user interaction or prior authentication, and it can be exploited locally (AV:L - Attack Vector: Local) with low attack complexity (AC:L). Successful exploitation results in a high impact on confidentiality, as sensitive files may be read without authorization, but it has limited impact on integrity and no impact on availability. The CVSS 3.1 base score is 6.8, indicating a medium severity level. No known exploits are currently reported in the wild, and no patches have been linked yet. The vulnerability's presence in the kernel file system module is critical because it operates at a low level with broad access to system resources, making unauthorized file access potentially severe. Given that HarmonyOS is Huawei's proprietary operating system used primarily on IoT devices, smartphones, and other smart devices, this vulnerability could expose sensitive data stored on affected devices if exploited by a local attacker or malicious application running on the device.

For European organizations, the impact of CVE-2025-31171 depends largely on the extent of HarmonyOS device deployment within their infrastructure or among employees. While HarmonyOS is less prevalent in Europe compared to Android or iOS, Huawei devices are present in some sectors, especially in telecommunications and IoT deployments. The vulnerability could lead to unauthorized disclosure of sensitive information stored on affected devices, including corporate data, credentials, or configuration files. This could facilitate further attacks such as privilege escalation or lateral movement within networks. Confidentiality breaches could have regulatory implications under GDPR if personal data is exposed. Additionally, organizations relying on Huawei IoT devices for critical infrastructure or industrial control could face risks if attackers access sensitive operational data. Although the attack vector is local, the risk increases if attackers gain physical access or can execute malicious code remotely through other vulnerabilities or social engineering. The absence of known exploits reduces immediate risk, but the medium severity score and potential confidentiality impact warrant proactive mitigation.

1. Immediate deployment of security updates or patches from Huawei once available is critical. Since no patches are currently linked, organizations should monitor Huawei security advisories closely. 2. Restrict physical access to devices running HarmonyOS to trusted personnel only, reducing the risk of local exploitation. 3. Implement strict application control policies to prevent installation or execution of unauthorized or untrusted applications that could exploit the vulnerability. 4. Employ device management solutions to monitor and control HarmonyOS devices, enabling rapid detection of suspicious activities or unauthorized file access attempts. 5. Conduct regular security audits and penetration testing focusing on Huawei devices to identify potential exploitation paths. 6. For organizations using Huawei IoT devices, segment these devices on separate network zones with limited access to sensitive systems to contain potential breaches. 7. Educate users about the risks of installing untrusted applications and the importance of device security hygiene. 8. Consider alternative devices or OS platforms where feasible, especially for high-risk environments, until the vulnerability is fully mitigated.