CVE-2025-20749 is a stack-based buffer overflow vulnerability classified under CWE-121, found in the charger component of numerous MediaTek System-on-Chips (SoCs), including MT6789, MT6835, MT6855, MT6878, MT6879, MT6886, MT6897, MT6899, MT6983, MT6985, MT6989, MT6991, MT8169, MT8188, MT8195, MT8196, MT8781, and MT8796. This vulnerability exists due to a missing bounds check in the charger module, which leads to an out-of-bounds write on the stack. The flaw can be exploited locally by an attacker who already has System-level privileges on an affected device, enabling escalation of privileges beyond the System level. No user interaction is required for exploitation, which increases the risk if an attacker gains initial access. The vulnerability affects Android versions 14.0, 15.0, and 16.0 running on these MediaTek chipsets. The CVSS v3.1 score is 6.7, indicating a medium severity with high impact on confidentiality, integrity, and availability, but limited by the requirement for high privileges to exploit. No public exploits are known at this time, and although a patch has been identified (ALPS09915493), it is not yet linked or widely available. The vulnerability could allow attackers to execute arbitrary code or corrupt memory, potentially leading to device compromise or denial of service. This issue highlights the importance of secure coding practices in low-level firmware components and the need for timely patching of mobile device firmware.

For European organizations, the impact of CVE-2025-20749 can be significant, particularly for those relying on Android devices powered by affected MediaTek chipsets. The vulnerability enables local privilege escalation, which could be leveraged by attackers who have already compromised a device at the System level to gain even greater control, potentially bypassing security controls and accessing sensitive data or disrupting device functionality. This can affect corporate mobile devices, IoT devices, or embedded systems using these chipsets, leading to data breaches, loss of device integrity, or service disruptions. Given the widespread use of MediaTek SoCs in consumer and enterprise mobile devices, organizations with mobile workforces or BYOD policies are at risk. The lack of required user interaction simplifies exploitation once initial access is gained. Although no known exploits exist currently, the vulnerability could be weaponized in targeted attacks or malware campaigns. This risk is heightened in sectors with sensitive data such as finance, healthcare, and government. Failure to patch promptly could expose organizations to advanced persistent threats and insider attacks leveraging this flaw to escalate privileges and move laterally within networks.

European organizations should implement a multi-layered mitigation strategy: 1) Prioritize deployment of firmware and OS updates from device manufacturers or MediaTek that address this vulnerability (patch ALPS09915493). 2) Maintain strict device management policies to limit System-level access and monitor for privilege escalation attempts on Android devices. 3) Employ mobile threat defense solutions capable of detecting anomalous behavior indicative of exploitation attempts. 4) Restrict installation of untrusted applications and enforce least privilege principles to reduce the likelihood of attackers gaining System privileges initially. 5) Conduct regular security audits and penetration tests focusing on mobile device security posture. 6) Educate users and administrators about the risks of privilege escalation vulnerabilities and the importance of timely updates. 7) For critical environments, consider isolating or restricting use of devices with affected MediaTek chipsets until patches are applied. 8) Collaborate with device vendors to obtain timely security updates and verify patch deployment status. These steps go beyond generic advice by focusing on controlling initial access, monitoring privilege use, and ensuring rapid patch management specific to the affected MediaTek platforms.