CVE-2021-0464
📋 TL;DR
This CVE describes a heap buffer overflow vulnerability in the Android sound trigger subsystem that allows local privilege escalation without user interaction. Attackers can exploit this to gain elevated privileges on affected Android devices. The vulnerability affects Android devices with specific kernel versions.
💻 Affected Systems
- Android devices
📦 What is this software?
Android by Google
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise allowing attackers to execute arbitrary code with kernel privileges, install persistent malware, or access sensitive data.
Likely Case
Local privilege escalation allowing attackers to bypass security restrictions and gain elevated system access on compromised devices.
If Mitigated
Limited impact if devices are patched or have additional security controls like SELinux enforcing mode and app sandboxing.
🎯 Exploit Status
Requires local access but no user interaction. Exploitation involves heap manipulation techniques.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: March 2021 Android security patch level or later
Vendor Advisory: https://source.android.com/security/bulletin/pixel/2021-03-01
Restart Required: Yes
Instructions:
1. Check for Android system updates in Settings > System > Advanced > System update. 2. Install March 2021 or later security patch. 3. Reboot device after installation.
🔧 Temporary Workarounds
Disable sound trigger service
androidTemporarily disable the vulnerable sound trigger subsystem to prevent exploitation
adb shell pm disable com.android.soundtrigger
🧯 If You Can't Patch
- Restrict installation of untrusted applications from unknown sources
- Implement application allowlisting and monitor for suspicious privilege escalation attempts
🔍 How to Verify
Check if Vulnerable:
Check Android security patch level in Settings > About phone > Android version. If patch level is earlier than March 2021, device is vulnerable.Check Version:
adb shell getprop ro.build.version.security_patchVerify Fix Applied:
Verify security patch level shows March 2021 or later date in Settings > About phone > Android version.📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs related to sound_trigger
- Unexpected privilege escalation attempts in audit logs
- Crash reports from sound trigger service
Network Indicators:
- None - this is a local vulnerability
SIEM Query:
source="android_kernel" AND ("sound_trigger" OR "CVE-2021-0464")