CVE-2025-20698 is a security vulnerability identified in the Power Hardware Abstraction Layer (HAL) of multiple MediaTek chipsets, including MT2718, MT6739, MT6761, MT6765, MT6768, MT6781, MT6789, MT6833, MT6835, MT6853, MT6855, MT6877, MT6878, MT6879, MT6883, MT6885, MT6886, MT6889, MT6893, MT6895, MT6897, MT6899, MT6983, MT6985, MT6989, MT6991, MT8186, MT8196, MT8391, MT8676, MT8678, MT8775, MT8786, MT8788E, MT8792, MT8796, MT8873, MT8883, and MT8893. The vulnerability is classified as CWE-787, an out-of-bounds write due to a missing bounds check in the Power HAL component. This flaw allows a local attacker, who already possesses System-level privileges, to perform an out-of-bounds write operation, potentially leading to an escalation of privileges beyond the System level. The vulnerability affects devices running Android versions 13.0, 14.0, and 15.0 on the aforementioned MediaTek platforms. Exploitation does not require user interaction, increasing the risk of automated or stealthy attacks. However, initial System-level privileges are a prerequisite, which limits the attack vector to scenarios where an attacker has already compromised the device to some extent. No known exploits are currently reported in the wild, and no CVSS score has been assigned yet. The issue was reserved in November 2024 and published in August 2025. The vulnerability is significant because out-of-bounds writes can corrupt memory, potentially allowing attackers to execute arbitrary code, cause denial of service, or bypass security controls. The absence of a patch link suggests that remediation may be pending or distributed through vendor-specific updates.

For European organizations, this vulnerability poses a risk primarily to mobile devices and embedded systems using affected MediaTek chipsets running Android 13 to 15. Organizations relying on smartphones, tablets, or IoT devices with these chipsets could face risks of privilege escalation attacks if an attacker gains System-level access, which could lead to full device compromise, data leakage, or disruption of services. This is particularly critical for sectors with sensitive data or critical infrastructure, such as finance, healthcare, and government agencies. The lack of user interaction required for exploitation increases the threat level in environments where devices might be exposed to malicious applications or insider threats. Additionally, the widespread use of MediaTek chipsets in budget and mid-range devices across Europe means that many endpoints could be vulnerable, potentially increasing the attack surface. The vulnerability could also impact supply chain security if compromised devices are used within corporate networks. However, since initial System privileges are required, the vulnerability is less likely to be exploited remotely without prior compromise, somewhat limiting its impact to post-exploitation scenarios.

To mitigate this vulnerability, European organizations should: 1) Prioritize patch management by monitoring MediaTek and device manufacturers for official security updates addressing CVE-2025-20698 and apply them promptly once available. 2) Implement strict application whitelisting and privilege management to prevent unauthorized elevation to System-level privileges, thereby reducing the risk of attackers reaching the prerequisite privilege level for exploitation. 3) Employ mobile device management (MDM) solutions to enforce security policies, restrict installation of untrusted applications, and monitor device integrity. 4) Conduct regular security audits and penetration testing focusing on privilege escalation vectors within mobile and embedded devices. 5) Educate users and administrators about the risks of installing unverified software and the importance of device security hygiene. 6) For critical environments, consider network segmentation and endpoint detection and response (EDR) tools capable of identifying suspicious local privilege escalation attempts. 7) Collaborate with vendors and supply chain partners to ensure devices are updated and secure before deployment. These measures go beyond generic advice by focusing on controlling the prerequisite conditions for exploitation and enhancing detection capabilities.