CVE-2025-20774 is a heap overflow vulnerability classified under CWE-122 affecting a broad range of MediaTek System on Chips (SoCs), 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 SoCs are integrated into many Android devices running versions 14.0 through 16.0. The vulnerability stems from a missing bounds check in the display subsystem, which allows an attacker with existing System privileges to perform an out-of-bounds write on the heap. This flaw can be exploited locally without requiring user interaction, enabling escalation of privileges beyond the System level, potentially to root or kernel privileges depending on the device architecture and security model. The CVSS v3.1 base score is 6.7, reflecting medium severity with high impact on confidentiality, integrity, and availability, but limited by the requirement of prior System-level access. The vulnerability does not appear to be exploited in the wild yet. The patch is referenced by MediaTek under ID ALPS10196993 but is not publicly linked in the provided data. The issue was reserved in November 2024 and published in December 2025. The vulnerability poses a significant risk in environments where attackers can gain System privileges, as it can be leveraged to fully compromise the device. The broad range of affected SoCs suggests a widespread impact across many Android devices using MediaTek chipsets.

The primary impact of CVE-2025-20774 is local privilege escalation on affected Android devices using MediaTek chipsets. An attacker who has already obtained System-level privileges can exploit this heap overflow to gain higher privileges, potentially full root or kernel-level access. This can lead to complete device compromise, allowing attackers to bypass security controls, access sensitive data, install persistent malware, or disrupt device functionality. Since the vulnerability affects many MediaTek SoCs integrated into a wide range of consumer and enterprise Android devices, the scope is extensive. The lack of user interaction requirement increases the risk in environments where attackers have some foothold. Organizations relying on MediaTek-powered devices for critical communications or operations could face data breaches, espionage, or service disruptions. Although no known exploits are currently reported, the medium CVSS score and the nature of the vulnerability warrant proactive mitigation to prevent future exploitation. The impact on confidentiality, integrity, and availability is high once exploited, but the initial access requirement limits the attack surface somewhat.

To mitigate CVE-2025-20774, organizations and device manufacturers should prioritize applying the official MediaTek patch ALPS10196993 as soon as it becomes available. Until patches are deployed, enforcing strict privilege separation and minimizing the number of processes or applications running with System-level privileges can reduce exploitation risk. Employing runtime protections such as heap integrity checks, address space layout randomization (ASLR), and control-flow integrity (CFI) can help detect or prevent exploitation attempts. Device administrators should audit and restrict applications or services that can escalate to System privileges, and monitor for suspicious local activity indicative of privilege escalation attempts. For enterprises deploying MediaTek-based devices, consider endpoint detection and response (EDR) solutions capable of identifying anomalous behavior related to heap overflows or privilege escalations. Regularly update device firmware and Android OS versions to incorporate security fixes. Finally, educating users and administrators about the risks of granting elevated privileges to untrusted applications can help reduce the initial access vector.