CVE-2021-0493
📋 TL;DR
This vulnerability allows local attackers to write beyond allocated memory boundaries in Android's memory management driver, potentially leading to privilege escalation. It affects Android devices using specific System-on-Chip (SoC) implementations. No user interaction is required for exploitation.
💻 Affected Systems
- Android devices with specific SoC implementations
📦 What is this software?
Android by Google
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise with root privileges, allowing installation of persistent malware, data theft, and bypassing all security controls.
Likely Case
Local privilege escalation enabling attackers to gain elevated permissions, access sensitive data, or install malicious applications.
If Mitigated
Limited impact if devices are patched, have SELinux enforcing mode, and follow Android security best practices.
🎯 Exploit Status
Requires local access and ability to execute code; no authentication bypass needed once local access is obtained.
🛠️ 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 system updates in Settings > System > System update. 2. Install May 2021 security patch or later. 3. Reboot device after installation.
🔧 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 to detect and block malicious applications
🧯 If You Can't Patch
- Isolate affected devices from sensitive networks and data
- Implement application allowlisting to prevent unauthorized app execution
🔍 How to Verify
Check if Vulnerable:
Check Android security patch level in Settings > About phone > Android security patch level. If earlier than May 2021, device is vulnerable.Check Version:
adb shell getprop ro.build.version.security_patchVerify Fix Applied:
Verify Android security patch level shows May 2021 or later in Settings > About phone > Android security patch level.📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs
- Memory corruption errors in dmesg
- SELinux denials for privilege escalation attempts
Network Indicators:
- Unusual outbound connections from privileged processes
- Unexpected privilege escalation patterns
SIEM Query:
source="android_logs" AND ("kernel panic" OR "out of bounds" OR "memory corruption")