CVE-2025-20798 is a vulnerability classified under CWE-787 (Out-of-bounds Write) affecting a wide range of MediaTek chipsets, including MT2718, MT6765, MT6768, MT6781, MT6833, MT6835, MT6853, MT6855, MT6877, MT6879, MT6893, MT6985, MT6989, MT6991, MT8186, MT8188, MT8196, MT8367, MT8391, MT8676, MT8678, MT8696, MT8766, MT8768, MT8781, MT8786, MT8788E, MT8791T, MT8792, MT8793, MT8796, MT8873, MT8883, and MT8893. These chipsets are integrated into many Android devices running versions 14.0 through 16.0. The vulnerability arises from a missing bounds check in the battery management component, which leads to an out-of-bounds write condition. This flaw can be exploited locally by an attacker who already has System-level privileges on the device, allowing them to escalate privileges further, potentially gaining full control over the device. The exploit does not require any user interaction, increasing the risk of automated or stealthy attacks. The CVSS v3.1 base score is 7.8, reflecting high severity with metrics AV:L (Local), AC:L (Low complexity), PR:L (Low privileges required), UI:N (No user interaction), and impacts rated high on confidentiality, integrity, and availability. Although no known exploits are currently reported in the wild, the vulnerability poses a significant risk if leveraged by malicious actors. The issue was reserved in November 2024 and published in January 2026, with patches identified by MediaTek under patch ID ALPS10315812. The vulnerability's presence in battery subsystem code is critical because battery management is a core system function, and corruption here can destabilize the device or allow persistent malicious control.

For European organizations, this vulnerability presents a significant risk primarily to mobile device security, especially for enterprises relying on Android devices with MediaTek chipsets for communication, authentication, or sensitive operations. Successful exploitation could lead to local privilege escalation, enabling attackers to bypass security controls, access confidential data, manipulate device integrity, or disrupt availability. This could impact sectors such as finance, healthcare, government, and critical infrastructure where mobile device security is paramount. The lack of user interaction requirement facilitates stealthy exploitation once System privileges are obtained, increasing the threat level. Additionally, the widespread use of MediaTek chipsets in mid-range and budget devices common in Europe means a broad attack surface. Organizations could face data breaches, espionage, or operational disruptions if attackers leverage this vulnerability in targeted campaigns or supply chain attacks. The absence of known exploits currently provides a window for proactive mitigation but also underscores the need for vigilance as exploit development could emerge rapidly.

1. Apply official security patches from device manufacturers or MediaTek as soon as they become available to remediate the out-of-bounds write flaw. 2. Restrict and monitor System-level privileges on devices to minimize the risk of attackers gaining the prerequisite access for exploitation. 3. Employ mobile device management (MDM) solutions to enforce security policies, control app installations, and detect anomalous behavior related to battery subsystem or privilege escalation attempts. 4. Conduct regular security audits and penetration testing focusing on privilege escalation vectors on Android devices within the organization. 5. Educate users and administrators about the risks of rooting or jailbreaking devices, which can increase exposure to System-level exploits. 6. Implement network segmentation and endpoint detection to limit lateral movement if a device is compromised. 7. Monitor threat intelligence feeds for emerging exploit code or attack campaigns targeting this CVE to enable rapid response. 8. Collaborate with device vendors to ensure timely updates and verify patch deployment status across the device fleet.