CVE-2025-20697 is a security vulnerability classified as CWE-787, an out-of-bounds write, found in the Power Hardware Abstraction Layer (HAL) of multiple MediaTek chipsets including MT2718, MT6761, MT6765, MT6768, MT6853, MT6855, MT6877, MT6878, MT6879, MT6883, MT6885, MT6889, MT6893, MT6897, MT6989, MT6991, MT8186, MT8196, MT8391, MT8678, MT8775, MT8786, MT8788E, MT8792, MT8796, MT8873, MT8883, and MT8893. These chipsets are widely used in mobile devices running Android versions 14.0 and 15.0. The vulnerability arises from a missing bounds check in the Power HAL, which can lead to an out-of-bounds write operation. This flaw can be exploited locally by an attacker who already possesses System-level privileges on the device, allowing them to escalate their privileges further. Notably, exploitation does not require any user interaction, increasing the risk in environments where an attacker has gained initial system access. The vulnerability impacts confidentiality, integrity, and availability, as indicated by the CVSS v3.1 score of 6.7 (medium severity) with vector AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H. This means the attack requires local access with high privileges but is relatively easy to execute once those conditions are met, and it can cause significant damage to the system's security posture. Although no known exploits are currently reported in the wild, the presence of this vulnerability in a critical system component like the Power HAL makes it a significant concern for device manufacturers and users. The absence of a patch link suggests that remediation may still be in progress or distributed through OEM updates. Given the broad range of affected chipsets, the vulnerability potentially affects a large number of devices globally, especially those using MediaTek SoCs in Android 14 and 15 devices.

For European organizations, the impact of CVE-2025-20697 can be substantial, particularly for enterprises relying on mobile devices powered by MediaTek chipsets. The vulnerability allows local privilege escalation from System to potentially higher privileges, which could enable attackers to bypass security controls, access sensitive data, or disrupt device operations. This is especially critical for sectors handling sensitive personal data or intellectual property, such as finance, healthcare, and government agencies. The lack of user interaction requirement means that once an attacker gains system-level access, they can exploit this vulnerability without alerting the user, increasing the risk of stealthy attacks. Moreover, given the widespread use of MediaTek chipsets in mid-range and budget devices popular in Europe, the vulnerability could affect a significant portion of mobile endpoints. This could lead to increased risk of data breaches, unauthorized access to corporate resources via mobile devices, and potential disruption of critical business communications. The vulnerability also poses a risk to supply chain security, as compromised devices could be used as footholds for broader network intrusions. Although no active exploits are reported, the medium severity rating and the nature of the vulnerability warrant proactive mitigation to prevent escalation scenarios that could compromise organizational security.

To mitigate CVE-2025-20697 effectively, European organizations should: 1) Prioritize updating device firmware and operating system versions as soon as MediaTek or device OEMs release patches addressing this vulnerability. Monitor vendor advisories and Android security bulletins closely. 2) Implement strict device management policies that limit the granting of System-level privileges to applications and users, reducing the attack surface for privilege escalation. 3) Employ mobile threat defense (MTD) solutions that can detect anomalous behavior indicative of privilege escalation attempts or exploitation of HAL vulnerabilities. 4) Enforce application whitelisting and restrict installation of untrusted or potentially malicious apps that could gain System privileges. 5) Conduct regular security audits and penetration testing on mobile devices to identify potential privilege escalation vectors. 6) Educate users and administrators about the risks of rooting or jailbreaking devices, which can increase exposure to such vulnerabilities. 7) For organizations with BYOD policies, enforce compliance checks to ensure devices are patched and secure before granting access to corporate resources. 8) Consider network segmentation and conditional access controls to limit the impact of compromised devices. These measures go beyond generic patching advice by focusing on privilege management, detection, and access control tailored to the nature of this vulnerability.