CVE-2025-20804 is a use-after-free vulnerability classified under CWE-416 affecting MediaTek chipsets MT6899 and MT6991. The flaw exists within the dpe component, where memory is freed prematurely but subsequently accessed, causing memory corruption. This corruption can be leveraged by an attacker who already has System-level privileges on the device to escalate their privileges further, potentially gaining higher control or bypassing security mechanisms. Exploitation requires local access and user interaction, which limits remote exploitation but still poses a significant risk in scenarios where an attacker has partial control or presence on the device. The vulnerability impacts confidentiality, integrity, and availability due to the potential for arbitrary code execution or system instability. The CVSS 3.1 base score is 6.7, reflecting a medium severity with low attack vector (local), low attack complexity, high privileges required, and no user interaction needed for the privilege escalation step itself. The vulnerability was published in early 2026, with no known exploits in the wild at this time. MediaTek has assigned patch ID ALPS10198951 to address this issue. The vulnerability highlights the importance of secure memory management in chipset firmware and drivers, especially in components like dpe that handle critical system functions.

The primary impact of CVE-2025-20804 is local privilege escalation on devices using affected MediaTek chipsets, which can lead to unauthorized access to sensitive system functions and data. This can compromise the confidentiality and integrity of the system by allowing attackers to execute arbitrary code with elevated privileges or disrupt system availability through memory corruption. Although exploitation requires prior System-level access and user interaction, it can be used as a stepping stone in multi-stage attacks to fully compromise a device. This is particularly concerning for mobile devices, IoT devices, and embedded systems relying on these chipsets, potentially affecting user data, device stability, and security controls. Organizations deploying these chipsets in consumer electronics, telecommunications infrastructure, or industrial systems face risks of targeted attacks or insider threats leveraging this vulnerability to deepen their control over affected devices.

To mitigate CVE-2025-20804, organizations should promptly apply the official patch ALPS10198951 provided by MediaTek or their device manufacturers. Since exploitation requires local System privileges and user interaction, enforcing strict access controls and minimizing privileged user accounts can reduce risk. Employing endpoint protection solutions that monitor for unusual privilege escalation attempts and memory corruption behaviors can provide additional defense. Regularly updating device firmware and drivers ensures vulnerabilities are addressed timely. For environments with high security requirements, consider implementing runtime memory protection mechanisms such as Control Flow Integrity (CFI) and Address Space Layout Randomization (ASLR) if supported by the chipset. Conduct thorough security audits on devices using these chipsets to detect any signs of compromise. Finally, educate users about the risks of interacting with untrusted software or content that could trigger the vulnerability.