CVE-2025-20773 is a use-after-free vulnerability classified under CWE-416 affecting the display subsystem of numerous MediaTek chipsets, including MT2718, MT6739, MT6761, MT6765, MT6768, MT6781, MT6789, MT6833, MT6835, MT6853, MT6855, MT6877, MT6878, MT6879, MT6883, MT6885, MT6886, MT6889, MT6893, MT6895, MT6897, MT6899, MT6983, MT6985, MT6989, MT6991, MT8196, MT8676, MT8678, MT8792, and MT8793. These chipsets are integrated into devices running Android versions 14.0, 15.0, and 16.0. The vulnerability arises from improper handling of memory in the display component, leading to use-after-free conditions that cause memory corruption. This corruption can be exploited to escalate privileges locally, but only if the attacker has already obtained System-level privileges on the device. Notably, exploitation does not require any user interaction, which means an attacker with system access can trigger the vulnerability without user involvement. The CVSS v3.1 score is 6.7 (medium severity), reflecting the vulnerability's impact on confidentiality, integrity, and availability, combined with the requirement for high privileges and no user interaction. No public exploits have been reported yet, and MediaTek has assigned patch ID ALPS10196993 to address the issue. The vulnerability is significant because it affects a broad range of MediaTek SoCs widely deployed in mobile devices, potentially impacting millions of users worldwide. The flaw could be leveraged in scenarios where an attacker has already compromised the device to gain even higher privileges, potentially leading to full device compromise or persistent control. The vulnerability highlights the importance of secure memory management in critical system components such as display drivers.

The primary impact of CVE-2025-20773 is local privilege escalation on devices using affected MediaTek chipsets running Android 14 to 16. An attacker who has already gained System-level privileges can exploit this vulnerability to further elevate their privileges, potentially gaining root or kernel-level access. This escalation can compromise device confidentiality by exposing sensitive data, integrity by allowing unauthorized modifications, and availability by causing system instability or crashes due to memory corruption. Although remote exploitation is not feasible without prior system access, the vulnerability poses a significant risk in environments where devices may be shared, multi-user, or already partially compromised. This can facilitate persistent malware installation, bypass of security controls, or unauthorized access to protected resources. Given the widespread deployment of MediaTek chipsets in smartphones, tablets, and IoT devices, the vulnerability could affect a large user base, especially in regions where these chipsets dominate the market. The absence of user interaction requirement increases the risk in automated or background attack scenarios. Organizations relying on devices with these chipsets should consider the risk of insider threats or malware that can leverage this flaw to deepen compromise.

1. Apply official patches from MediaTek or device manufacturers as soon as they become available, specifically the patch identified by ALPS10196993. 2. Restrict and monitor system-level privileges rigorously to prevent unauthorized users or applications from obtaining System privileges, which are required to exploit this vulnerability. 3. Employ runtime protections such as memory corruption mitigations (e.g., Address Space Layout Randomization (ASLR), Control Flow Integrity (CFI)) where supported by the device firmware or OS. 4. Implement strict application sandboxing and privilege separation to minimize the risk of privilege escalation from compromised apps. 5. Conduct regular security audits and monitoring on devices to detect unusual local privilege escalations or memory corruption symptoms. 6. Educate users and administrators about the risks of installing untrusted applications or rooting devices, which can increase exposure to this vulnerability. 7. For organizations deploying devices with these chipsets, consider endpoint detection and response (EDR) solutions capable of detecting local privilege escalation attempts. 8. Coordinate with device vendors to ensure timely firmware and OS updates and verify patch deployment status across the device fleet.