CVE-2025-48638
📋 TL;DR
CVE-2025-48638 is a kernel vulnerability in Android's pKVM (protected Kernel-based Virtual Machine) tracing subsystem that allows local privilege escalation without user interaction. An out-of-bounds write in the __pkvm_load_tracing function enables attackers to gain elevated privileges from an unprivileged local context. This affects Android devices with vulnerable kernel versions.
💻 Affected Systems
- Android devices with vulnerable kernel versions
📦 What is this software?
Android by Google
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise allowing attackers to gain root/kernel privileges, install persistent malware, bypass security controls, and access all user data.
Likely Case
Local privilege escalation allowing malware to elevate privileges and bypass application sandboxing to access sensitive data or system resources.
If Mitigated
Limited impact if SELinux/AppArmor policies restrict the vulnerable component or if the device has additional kernel hardening features enabled.
🎯 Exploit Status
Requires local access but no user interaction. Exploitation involves triggering the out-of-bounds write through improper input validation in the tracing subsystem.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Android Security Bulletin December 2025 patch level
Vendor Advisory: https://source.android.com/security/bulletin/2025-12-01
Restart Required: Yes
Instructions:
1. Check for Android system updates in Settings > System > System update. 2. Apply the December 2025 security patch. 3. Reboot the device. 4. Verify the patch level in Settings > About phone > Android version > Security patch level.
🔧 Temporary Workarounds
Disable pKVM tracing (if supported)
linuxDisable the vulnerable pKVM tracing subsystem if device configuration allows it
echo 0 > /sys/kernel/debug/tracing/events/pkvm/enable
🧯 If You Can't Patch
- Restrict local access to devices and implement application allowlisting to prevent malicious apps from running
- Enable additional kernel hardening features and monitor for privilege escalation attempts
🔍 How to Verify
Check if Vulnerable:
Check kernel version and security patch level: adb shell getprop ro.build.version.security_patchCheck Version:
adb shell uname -r && adb shell getprop ro.build.version.security_patchVerify Fix Applied:
Verify security patch level shows December 2025 or later: adb shell getprop ro.build.version.security_patch📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs
- Unexpected privilege escalation attempts in audit logs
- SELinux/AppArmor denials related to pkvm or tracing
Network Indicators:
- None - this is a local vulnerability
SIEM Query:
source="android_kernel" AND ("pkvm" OR "trace.c" OR "privilege escalation")