CVE-2025-20775 Overview
CVE-2025-20775 is a use-after-free vulnerability [CWE-416] in the MediaTek display component used by Google Android devices. The flaw can lead to memory corruption and local escalation of privilege. According to MediaTek, exploitation requires that an attacker has already obtained System privilege on the device. User interaction is not required. The issue is tracked under MediaTek Patch ID ALPS10182914 and Issue ID MSV-4795, and affects dozens of MediaTek chipsets running Android 14, 15, and 16.
Critical Impact
A local attacker with System privilege can corrupt memory in the display driver to escalate privileges further on affected MediaTek-powered Android devices.
Affected Products
- Google Android 14, 15, and 16
- MediaTek smartphone 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
- MediaTek tablet and AIoT chipsets including MT8186, MT8188, MT8196, MT8667, MT8673, MT8676, MT8678, MT8765, MT8766, MT8768, MT8771, MT8781, MT8791T, MT8792, MT8793, MT8795T, MT8796, MT8798, MT8873, MT8883
Discovery Timeline
- 2025-12-02 - CVE-2025-20775 published to NVD alongside the MediaTek Product Security Bulletin
- 2026-01-12 - Last updated in NVD database
Technical Details for CVE-2025-20775
Vulnerability Analysis
The vulnerability resides in the MediaTek display driver shipped on Android devices. A use-after-free condition occurs when code continues to reference a memory object after it has been released back to the allocator. An attacker who triggers the freed object reuse can manipulate the contents of that memory region before the dangling pointer is dereferenced. This results in memory corruption inside a privileged execution context.
The attack vector is local. MediaTek states the attacker must already hold System privilege to reach the vulnerable code path. The flaw therefore acts as a privilege escalation primitive rather than an initial compromise vector. A successful exploit can elevate execution from the System user context toward kernel or driver-level privileges, undermining the Android permission boundary.
Root Cause
The root cause is improper object lifetime management in the MediaTek display driver, classified under [CWE-416] Use After Free. The driver releases a memory allocation while retaining at least one reference that is later dereferenced. Because the surrounding code path does not require user interaction, exploitation can be triggered programmatically by a malicious process already running with System privileges.
Attack Vector
Exploitation requires local code execution at System privilege on the device. A malicious application, or a previously compromised system service, invokes the affected display driver interface and triggers the dangling pointer dereference. By spraying the freed slab slot with attacker-controlled data, the adversary can corrupt kernel-visible structures and pivot to higher privilege. No remote network access and no user tap or consent is required during the exploitation step itself. Refer to the MediaTek Security Bulletin December 2025 for the technical scope of the affected driver path.
Detection Methods for CVE-2025-20775
Indicators of Compromise
- Unexpected crashes or tombstone files in /data/tombstones/ referencing the MediaTek display driver or SIGSEGV in display-related kernel symbols.
- Kernel log (dmesg, logcat -b kernel) entries showing slab corruption, KASAN reports, or oops messages tied to the display subsystem.
- Processes running as system UID making anomalous ioctl calls to display device nodes such as /dev/mtk_disp*.
Detection Strategies
- Compare the device's Android security patch level against the December 2025 MediaTek bulletin to identify unpatched fleet devices.
- Hunt for non-OEM applications or services that attempt to interact with privileged MediaTek display interfaces.
- Correlate repeated display-driver crashes with subsequent unauthorized privilege changes or new root-equivalent processes.
Monitoring Recommendations
- Centralize Android device telemetry, including kernel logs and crash reports, in a SIEM or data lake for longitudinal analysis.
- Alert on creation of processes running outside the expected system_server lineage when they hold System privilege.
- Track Mobile Device Management (MDM) compliance for the December 2025 Android security patch level across all MediaTek-based devices.
How to Mitigate CVE-2025-20775
Immediate Actions Required
- Apply the December 2025 Android security patch level on all MediaTek-powered devices in the fleet.
- Verify OEM firmware updates incorporate MediaTek Patch ID ALPS10182914 for Issue ID MSV-4795.
- Enforce MDM policies that block sideloading and restrict installation of applications from untrusted sources.
Patch Information
MediaTek has released a fix tracked as Patch ID ALPS10182914. The patch is distributed to OEMs and rolled out through device vendor firmware updates. Details are documented in the MediaTek Security Bulletin December 2025. Administrators should require devices to report an Android security patch level of December 2025 or later before granting access to corporate resources.
Workarounds
- No vendor-supplied workaround is available; patching is the only supported remediation.
- Reduce exposure by restricting which applications and services run with elevated privileges on managed Android devices.
- Retire or isolate end-of-life devices that will not receive the December 2025 patch from their OEM.
# Verify Android security patch level via adb
adb shell getprop ro.build.version.security_patch
# Expected output: 2025-12-01 or later for affected MediaTek devices
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
