CVE-2025-36938
📋 TL;DR
This CVE describes a fault injection vulnerability in U-Boot's append_uint32_le() function that could allow physical attackers to escalate privileges without user interaction. The vulnerability affects systems using vulnerable U-Boot versions, particularly Android devices with Pixel firmware. Exploitation requires physical access to the device.
💻 Affected Systems
- Android Pixel devices
- Systems using vulnerable U-Boot versions
📦 What is this software?
Android by Google
⚠️ Risk & Real-World Impact
Worst Case
Physical attacker gains full control of the device boot process, potentially bypassing secure boot and installing persistent malware.
Likely Case
Physical attacker with specialized equipment could bypass boot security to gain elevated privileges on affected devices.
If Mitigated
With physical security controls and secure boot enabled, impact is limited to devices with direct physical access.
🎯 Exploit Status
Exploitation requires physical access and fault injection equipment. No authentication needed but requires specialized hardware for timing/power analysis attacks.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Android Security Patch Level December 2025
Vendor Advisory: https://source.android.com/security/bulletin/pixel/2025-12-01
Restart Required: Yes
Instructions:
1. Apply December 2025 Android security update
2. For Pixel devices: Settings > System > System update
3. For other devices: Check manufacturer for U-Boot updates
4. Reboot device after update
🔧 Temporary Workarounds
Physical Security Controls
allImplement physical security measures to prevent unauthorized physical access to devices
Secure Boot Enforcement
allEnsure secure boot is enabled and properly configured
🧯 If You Can't Patch
- Restrict physical access to vulnerable devices
- Implement device tamper detection and monitoring
🔍 How to Verify
Check if Vulnerable:
Check Android security patch level: Settings > About phone > Android version > Security patch levelCheck Version:
adb shell getprop ro.build.version.security_patchVerify Fix Applied:
Verify security patch level shows December 2025 or later📡 Detection & Monitoring
Log Indicators:
- Unexpected device reboots
- Bootloader modification attempts
- Secure boot violations
SIEM Query:
Device boot events with suspicious timing or secure boot failures