CVE-2021-0489
📋 TL;DR
This CVE describes a memory management driver vulnerability in Android System-on-Chip (SoC) devices where missing bounds checking allows out-of-bounds writes. An attacker could exploit this to gain local privilege escalation without requiring user interaction or additional execution privileges. This affects Android devices using vulnerable SoC implementations.
💻 Affected Systems
- Android devices with vulnerable SoC implementations
📦 What is this software?
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 bypass security controls.
Likely Case
Local privilege escalation allowing malware or malicious apps to gain elevated permissions, access sensitive data, or perform unauthorized actions.
If Mitigated
Limited impact if device is fully patched, has security features like SELinux properly configured, and runs minimal privileged services.
🎯 Exploit Status
Requires local access to device; no user interaction needed but attacker needs ability to execute code on device.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: May 2021 Android Security Bulletin or later
Vendor Advisory: https://source.android.com/security/bulletin/2021-05-01
Restart Required: Yes
Instructions:
1. Check for Android security updates in device Settings > System > Advanced > System update. 2. Install May 2021 or later security patch. 3. Reboot device after installation. 4. Verify patch applied via Settings > About phone > Android security patch level.
🔧 Temporary Workarounds
Restrict app installations
androidOnly install apps from trusted sources like Google Play Store to reduce attack surface
Enable Google Play Protect
androidEnsure Google Play Protect is enabled for malware scanning
🧯 If You Can't Patch
- Isolate vulnerable devices on separate network segments
- Implement strict application allowlisting and device management policies
🔍 How to Verify
Check if Vulnerable:
Check Android security patch level in Settings > About phone > Android security patch level. If date is before May 2021, device is likely vulnerable.Check Version:
adb shell getprop ro.build.version.security_patchVerify Fix Applied:
Verify Android security patch level shows May 2021 or later date in Settings > About phone > Android security patch level.📡 Detection & Monitoring
Log Indicators:
- Unusual privilege escalation attempts in system logs
- Suspicious memory access patterns in kernel logs
- Unexpected driver or system service crashes
Network Indicators:
- Unusual outbound connections from system processes
- Suspicious network activity from elevated privileges
SIEM Query:
source="android_system_logs" AND (event_type="privilege_escalation" OR process_name="kernel") AND message="*out of bounds*" OR "*memory corruption*"