CVE-2025-20785: 
NixOS vulnerability analysis and mitigation

CVE-2025-20785 is a use-after-free memory corruption vulnerability in the display component of MediaTek chipsets affecting Android 14.0, 15.0, and 16.0. It was disclosed on January 5, 2026, by MediaTek, Inc. and published to NVD on January 6, 2026. The vulnerability affects over 50 MediaTek chipsets including 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, MT8186, MT8188, MT8196, MT8667, MT8673, MT8676, MT8678, MT8765, MT8766, MT8768, MT8771, MT8781, MT8791T, MT8792, MT8793, MT8795T, MT8796, MT8798, MT8873, and MT8883. It carries a CVSS v3.1 base score of 6.7 (Medium) (MediaTek Advisory, Red Hat CVE).

The vulnerability is classified as CWE-416 (Use After Free), occurring in the display subsystem of MediaTek SoCs running Android. A use-after-free condition arises when memory that has been freed is subsequently accessed, potentially allowing an attacker to corrupt memory and redirect code execution. Exploitation requires the attacker to have already obtained System-level privileges on the device, and no user interaction is needed. The patch is identified as ALPS10149882 (Issue ID: MSV-4677) (MediaTek Advisory).

Successful exploitation allows a local attacker with System privileges to escalate privileges further, with high impact to confidentiality, integrity, and availability. The memory corruption could enable unauthorized access to sensitive data, unauthorized system modifications, and potential denial of service conditions on the affected device. The scope is limited to the local device, but the breadth of affected chipsets means a wide range of Android smartphones and tablets could be impacted (MediaTek Advisory, Red Hat CVE).

There is no public proof-of-concept exploit available, and no evidence of in-the-wild exploitation has been reported as of the time of disclosure. The EPSS score is approximately 0.018%, indicating a very low probability of exploitation in the near term. The vulnerability is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog. Exploitation is constrained by the requirement for the attacker to already possess System-level privileges, significantly limiting the attack surface (MediaTek Advisory).

MediaTek has released a patch (Patch ID: ALPS10149882; Issue ID: MSV-4677) addressed in the MediaTek Product Security Bulletin for January 2026. Device manufacturers and OEMs should integrate and distribute this patch to affected devices running Android 14.0, 15.0, and 16.0 on the listed chipsets. Lenovo has also published a vendor advisory for affected MediaTek-based tablets. Organizations should prioritize applying available security updates, restrict System-level privilege access where possible, and monitor for signs of exploitation (MediaTek Advisory, Lenovo Advisory).