CVE-2025-20771 Overview
CVE-2025-20771 is a local privilege escalation vulnerability affecting the display driver component in Google Android devices running on MediaTek chipsets. The vulnerability stems from improper input validation (CWE-457: Use of Uninitialized Variable) in the display subsystem, which could allow an attacker who has already obtained System-level privileges to escalate to higher privileges. Exploitation does not require user interaction, making this vulnerability particularly concerning for enterprise and consumer Android devices.
This vulnerability has been assigned a CVSS v3.1 score of 6.7 (Medium severity) with the vector string CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H, indicating high impact on confidentiality, integrity, and availability despite requiring high privileges as a prerequisite.
Critical Impact
A malicious actor with System privileges can leverage improper input validation in the display driver to achieve local privilege escalation, potentially gaining kernel-level access and full device compromise across a wide range of MediaTek-powered Android devices.
Affected Products
- Google Android 14.0, 15.0, 16.0
- MediaTek MT6739, MT6761, MT6765, MT6768, MT6781, MT6789
- MediaTek MT6833, MT6835, MT6853, MT6855, MT6877, MT6878
- MediaTek MT6879, MT6883, MT6885, MT6886, MT6889, MT6893
- MediaTek MT6895, MT6897, MT6899, MT6983, MT6985, MT6989, MT6991
- MediaTek MT2718, MT8196, MT8676, MT8678, MT8792, MT8793
Discovery Timeline
- 2025-12-02 - CVE-2025-20771 published to NVD
- 2025-12-03 - Last updated in NVD database
Technical Details for CVE-2025-20771
Vulnerability Analysis
The vulnerability exists within the display driver component used across numerous MediaTek chipsets. According to the security advisory, improper input validation in the display subsystem allows for potential privilege escalation. The issue is tracked internally by MediaTek as Patch ID: ALPS10196993 and Issue ID: MSV-4802.
The vulnerability is classified under CWE-457 (Use of Uninitialized Variable), suggesting that the display driver fails to properly initialize or validate input data before processing, leading to a condition where uninitialized memory can be leveraged by an attacker. This type of vulnerability in kernel-level drivers is particularly dangerous as it can provide a pathway from user-space System privileges to kernel execution context.
The EPSS (Exploit Prediction Scoring System) probability for this vulnerability is 0.005% with a percentile ranking of 24.3%, indicating a relatively low likelihood of exploitation in the wild at this time.
Root Cause
The root cause of CVE-2025-20771 is improper input validation within the MediaTek display driver. Specifically, the vulnerability relates to the use of uninitialized variables (CWE-457), where input parameters passed to the display driver are not properly validated or sanitized before being processed. This can result in the driver operating on uninitialized or attacker-controlled memory regions, creating an exploitable condition for privilege escalation.
The display driver, being a privileged kernel component responsible for managing display hardware operations, processes commands and data structures from higher-level Android components. When input validation is insufficient, malformed or crafted input can corrupt memory state or influence control flow.
Attack Vector
The attack vector is local (AV:L), requiring the attacker to have existing access to the device with System-level privileges. The attack complexity is low (AC:L), meaning no special conditions or circumstances are required beyond the prerequisite privilege level. No user interaction is needed for exploitation (UI:N).
An attacker with System privileges could exploit this vulnerability by sending specially crafted requests or data to the display driver through exposed interfaces (such as ioctl calls or memory-mapped operations). By manipulating input parameters that are not properly validated, the attacker can trigger the use of uninitialized memory, potentially leading to arbitrary code execution in the kernel context.
Detection Methods for CVE-2025-20771
Indicators of Compromise
- Unusual display driver activity or unexpected ioctl calls to /dev/ display device nodes
- Anomalous kernel log entries related to the MediaTek display driver ([display] or similar tags)
- Unexpected privilege transitions from System to kernel context
- Memory access violations or crashes in the display subsystem
- Suspicious processes attempting to interact with display driver interfaces
Detection Strategies
Organizations should implement monitoring for suspicious interactions with MediaTek display driver components. Key detection strategies include:
Kernel-Level Monitoring: Deploy kernel integrity monitoring solutions to detect unauthorized modifications to display driver code or data structures. Monitor for anomalous system calls targeting display device nodes.
Behavioral Analysis: Implement behavioral detection rules to identify processes with System privileges exhibiting unusual patterns of interaction with display subsystem interfaces, particularly high volumes of ioctl operations or memory mapping requests.
Log Analysis: Configure centralized logging to capture and analyze kernel messages from the display driver subsystem. Look for error conditions, memory access violations, or crash dumps that could indicate exploitation attempts.
Monitoring Recommendations
Security teams should prioritize the following monitoring activities:
- Enable verbose logging for kernel drivers where possible and forward to SIEM platforms
- Implement Mobile Threat Defense (MTD) solutions capable of detecting privilege escalation attempts on Android devices
- Monitor for any publicly released proof-of-concept exploits targeting CVE-2025-20771
- Track MediaTek security bulletins for additional technical indicators
SentinelOne Singularity Mobile provides comprehensive protection against privilege escalation attacks on Android devices, offering real-time behavioral analysis and kernel-level threat detection capabilities.
How to Mitigate CVE-2025-20771
Immediate Actions Required
- Apply the December 2025 security patch from MediaTek/device OEMs immediately
- Verify device firmware includes Patch ID ALPS10196993
- Implement Mobile Device Management (MDM) policies to enforce security updates
- Restrict installation of applications from unknown sources
- Monitor devices for signs of compromise or unusual behavior
- Prioritize patching for devices with sensitive data or access to corporate resources
Patch Information
MediaTek has released a security patch addressing this vulnerability in their December 2025 Product Security Bulletin. The patch is identified as ALPS10196993 and addresses the improper input validation issue in the display driver.
Device manufacturers (OEMs) will integrate this patch into their Android security updates. Users should check with their device manufacturer for the availability of firmware updates containing this fix. For Google Pixel devices using MediaTek chipsets, the patch will be included in the Android Security Bulletin.
Reference: MediaTek Product Security Bulletin - December 2025
Workarounds
As this vulnerability resides in the kernel display driver and requires System-level privileges as a prerequisite, traditional application-level workarounds are limited. However, organizations can implement defense-in-depth strategies:
- Minimize Attack Surface: Limit the number of applications running with elevated privileges on affected devices
- Application Vetting: Implement strict application allowlisting to prevent malicious apps from gaining System privileges
- Network Segmentation: Isolate affected devices from sensitive network resources until patches are applied
- Endpoint Protection: Deploy mobile endpoint protection solutions that can detect and prevent privilege escalation attempts
# Verify Android security patch level via ADB
adb shell getprop ro.build.version.security_patch
# Check for MediaTek chipset identification
adb shell cat /proc/cpuinfo | grep Hardware
# Monitor kernel logs for display driver anomalies
adb shell dmesg | grep -i display
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
