CVE-2025-20797 is a stack overflow vulnerability classified under CWE-121, found in the battery component of MediaTek chipsets. The root cause is a missing bounds check that allows an out-of-bounds write operation on the stack. This vulnerability affects a broad range of MediaTek chipsets, including models MT2718 through MT8893, which are widely deployed in smartphones, IoT devices, and embedded systems. The vulnerability requires that an attacker already possesses System-level privileges on the device, meaning it is a local privilege escalation vector rather than a remote attack. No user interaction is needed, which simplifies exploitation once System access is gained. The CVSS v3.1 base score is 7.8, reflecting high severity due to the potential for full compromise of confidentiality, integrity, and availability. The flaw could allow an attacker to escalate privileges further, potentially gaining kernel-level control or executing arbitrary code with elevated rights. Although no known exploits are currently reported in the wild, the vulnerability poses a significant risk given the widespread use of affected chipsets. The vendor has assigned a patch ID (ALPS10315812) but no public patch links are currently available. Organizations should monitor for updates and apply patches promptly to mitigate risks.

The impact of CVE-2025-20797 is significant for organizations relying on devices powered by affected MediaTek chipsets. Since the vulnerability allows local privilege escalation from System-level privileges, attackers who have already compromised a device at a moderate privilege level can leverage this flaw to gain full control, potentially leading to unauthorized access to sensitive data, disruption of device functionality, or persistent malware installation. This can affect mobile devices, IoT endpoints, and embedded systems, which are often used in enterprise, industrial, and consumer environments. The compromise of such devices can lead to data breaches, operational disruptions, and increased attack surface for lateral movement within networks. Given the absence of required user interaction, automated local exploits could be developed, increasing the risk. The broad chipset coverage means a large number of devices globally are potentially vulnerable, amplifying the threat to supply chains and critical infrastructure that depend on these components.

To mitigate CVE-2025-20797, organizations should: 1) Apply official patches from MediaTek or device manufacturers as soon as they become available, referencing patch ID ALPS10315812. 2) Restrict System-level access on devices to trusted administrators only, minimizing the risk that an attacker can reach the privilege level needed to exploit the vulnerability. 3) Implement robust endpoint detection and response (EDR) solutions to monitor for suspicious local privilege escalation attempts or anomalous behavior indicative of exploitation. 4) Employ application whitelisting and least privilege principles to reduce the attack surface. 5) For IoT and embedded devices, ensure secure firmware update mechanisms are in place to facilitate timely patch deployment. 6) Conduct regular security audits and penetration testing focusing on privilege escalation vectors. 7) Educate users and administrators about the risks of local privilege escalation and the importance of maintaining device hygiene. These steps go beyond generic advice by emphasizing access control, monitoring, and secure update practices tailored to the affected chipset environment.