CVE-2021-0881
📋 TL;DR
This CVE describes an integer overflow vulnerability in the PowerVR kernel driver for Android devices. It allows local attackers to gain escalated privileges without user interaction, potentially taking full control of affected devices. The vulnerability affects Android devices using specific PowerVR GPU hardware.
💻 Affected Systems
- Android devices with PowerVR GPU hardware
📦 What is this software?
Android by Google
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise with root/kernel-level access, allowing installation of persistent malware, data theft, and bypassing of all security controls.
Likely Case
Local privilege escalation enabling attackers to bypass app sandboxing, access sensitive data, and install malicious apps with elevated permissions.
If Mitigated
Limited impact if devices are patched, have SELinux enforcing mode, and follow principle of least privilege for apps.
🎯 Exploit Status
Requires local access and ability to execute code on device. Kernel driver vulnerabilities typically require some technical sophistication to exploit.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Android security updates from April 2023 onward
Vendor Advisory: https://source.android.com/security/bulletin/2023-04-01
Restart Required: Yes
Instructions:
1. Check for Android security updates in device settings. 2. Install April 2023 or later security patch. 3. Reboot device after installation. 4. Verify patch level in About Phone settings.
🔧 Temporary Workarounds
Restrict app permissions
androidLimit app installations to trusted sources and review app permissions to reduce attack surface
Enable Google Play Protect
androidEnsure Google Play Protect is active to detect potentially harmful apps
🧯 If You Can't Patch
- Isolate affected devices from sensitive networks and data
- Implement strict app installation policies and monitor for suspicious activity
🔍 How to Verify
Check if Vulnerable:
Check Android security patch level in Settings > About Phone > Android version. If before April 2023, device may be vulnerable.Check Version:
adb shell getprop ro.build.version.security_patchVerify Fix Applied:
Verify security patch level shows April 2023 or later date in About Phone settings.📡 Detection & Monitoring
Log Indicators:
- Kernel crash logs
- SELinux denials related to PowerVR driver
- Unexpected privilege escalation attempts
Network Indicators:
- None (local exploit only)
SIEM Query:
Look for kernel panic events or SELinux audit logs containing 'PVRSRV' or 'RGX' strings