CVE-2025-20802 is a use-after-free vulnerability classified under CWE-416 found in the geniezone component of MediaTek chipsets, specifically impacting models MT6991, MT8196, MT8367, MT8781, MT8786, and MT8793. The vulnerability arises from improper handling of memory, where a previously freed memory region is accessed, leading to memory corruption. This corruption can be exploited by an attacker who already possesses System-level privileges on the device to escalate their privileges further, potentially gaining deeper control or bypassing security mechanisms. The flaw does not require any user interaction to be exploited, but it does require the attacker to have already achieved a high privilege level, limiting the initial attack vector to local threat actors or malware with elevated rights. The vulnerability affects confidentiality, integrity, and availability of the system, as it can lead to arbitrary code execution or system instability. The CVSS v3.1 score of 6.7 reflects a medium severity, with attack vector local, low attack complexity, high privileges required, no user interaction, and impacts rated high across confidentiality, integrity, and availability. No public exploits have been reported to date, but the presence of such a vulnerability in widely deployed chipsets necessitates prompt patching. The issue is tracked under MediaTek’s internal patch ID ALPS10238968 and issue ID MSV-4914. Due to the chipset’s broad use in mobile devices, IoT, and embedded systems, the vulnerability has a wide potential impact.

The primary impact of CVE-2025-20802 is local privilege escalation on devices using affected MediaTek chipsets. An attacker who has already compromised the system at a high privilege level can exploit this vulnerability to gain further control, potentially bypassing security controls, accessing sensitive data, or causing system instability or denial of service. This can lead to complete system compromise in embedded devices, smartphones, or IoT devices relying on these chipsets. The vulnerability affects confidentiality, integrity, and availability, increasing the risk of data breaches, unauthorized access, and operational disruptions. Organizations deploying devices with these chipsets, including telecom providers, device manufacturers, and enterprises using embedded systems, face risks of targeted attacks or malware leveraging this flaw to deepen footholds. Although exploitation requires prior elevated access, the lack of user interaction lowers the barrier for automated or scripted attacks once initial compromise occurs. The absence of known exploits currently reduces immediate risk but does not eliminate the threat of future exploitation. The broad deployment of affected chipsets globally means a large attack surface exists, especially in consumer electronics and industrial IoT sectors.

To mitigate CVE-2025-20802, organizations and device manufacturers should prioritize applying the official patch identified by MediaTek as ALPS10238968 as soon as it becomes available. Until patches are deployed, restrict local access to devices running affected chipsets to trusted personnel only, minimizing the risk of privilege escalation by limiting potential attackers. Employ robust endpoint protection and monitoring to detect unusual local privilege escalation attempts or memory corruption indicators. Implement strict access controls and privilege management to reduce the likelihood that an attacker can obtain System-level privileges initially. For embedded and IoT devices, consider network segmentation and isolation to limit lateral movement if a device is compromised. Device manufacturers should integrate secure coding practices and conduct thorough memory safety testing to prevent similar use-after-free vulnerabilities in future chipset firmware. Additionally, maintain up-to-date inventories of devices using affected chipsets to ensure comprehensive patch management. Finally, monitor threat intelligence sources for any emerging exploit code or attack campaigns targeting this vulnerability to respond promptly.