CVE-2021-0329
📋 TL;DR
This CVE describes a memory corruption vulnerability in Android's Bluetooth stack where missing bounds checks in native functions could allow out-of-bounds writes. An attacker with local access could exploit this to escalate privileges on affected Android devices. The vulnerability affects Android versions 8.1 through 11.
💻 Affected Systems
- Android
📦 What is this software?
Android by Google
Android by Google
Android by Google
Android by Google
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise allowing attacker to gain root/system privileges, install persistent malware, access all user data, and potentially use device as pivot point in network.
Likely Case
Local privilege escalation allowing attacker to bypass app sandbox, access sensitive data from other apps, and potentially install malicious apps with elevated permissions.
If Mitigated
Limited impact if Bluetooth is disabled or device is fully patched; attacker would need physical access or malware already installed with user privileges.
🎯 Exploit Status
Exploitation requires user execution privileges initially. No public exploit code is known, but the vulnerability type (out-of-bounds write) is commonly exploited for privilege escalation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Android Security Bulletin February 2021 patches
Vendor Advisory: https://source.android.com/security/bulletin/2021-02-01
Restart Required: Yes
Instructions:
1. Check for Android system updates in Settings > System > Advanced > System update. 2. Install February 2021 security patch or later. 3. Reboot device after installation. 4. Verify patch level in Settings > About phone > Android security patch level.
🔧 Temporary Workarounds
Disable Bluetooth
androidTemporarily disable Bluetooth to prevent exploitation until patch can be applied
Settings > Connected devices > Connection preferences > Bluetooth > Turn off
🧯 If You Can't Patch
- Disable Bluetooth when not in use to reduce attack surface
- Restrict physical access to devices and implement mobile device management (MDM) policies
🔍 How to Verify
Check if Vulnerable:
Check Android security patch level: Settings > About phone > Android security patch level. If date is before February 2021, device is vulnerable.Check Version:
adb shell getprop ro.build.version.security_patchVerify Fix Applied:
Verify Android security patch level shows February 2021 or later date.📡 Detection & Monitoring
Log Indicators:
- Unusual Bluetooth service crashes
- Privilege escalation attempts in system logs
- Suspicious native process execution
Network Indicators:
- Unusual Bluetooth pairing attempts
- Abnormal Bluetooth service behavior
SIEM Query:
source="android_system" AND (event="bluetooth_crash" OR event="privilege_escalation")