CVE-2021-0701
📋 TL;DR
This vulnerability is an integer overflow in the PowerVR kernel driver that allows out-of-bounds heap access. It enables local privilege escalation without requiring user interaction or additional execution privileges. Affected systems include Android devices with vulnerable PowerVR GPU drivers.
💻 Affected Systems
- Android devices with PowerVR GPU hardware
📦 What is this software?
Android by Google
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with root privileges, allowing complete control over the device, data theft, and persistence.
Likely Case
Local privilege escalation to gain root access on compromised devices, enabling further malicious activities.
If Mitigated
Limited impact if SELinux/AppArmor policies restrict kernel module loading and device is not rooted.
🎯 Exploit Status
Requires local access but no user interaction. Kernel exploitation requires bypassing modern mitigations like KASLR, stack canaries.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: June 2023 Android Security Patch or later
Vendor Advisory: https://source.android.com/security/bulletin/2023-06-01
Restart Required: Yes
Instructions:
1. Check for Android system updates in Settings > System > System update. 2. Apply June 2023 or later security patch. 3. Reboot device after update completes.
🔧 Temporary Workarounds
Restrict kernel module loading
linuxPrevent loading of unauthorized kernel modules to limit exploitation vectors
echo 1 > /proc/sys/kernel/modules_disabled
🧯 If You Can't Patch
- Implement strict application vetting and only install apps from trusted sources
- Use mobile device management (MDM) to enforce security 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 June 2023, device is vulnerable.Check Version:
adb shell getprop ro.build.version.security_patchVerify Fix Applied:
Verify security patch level shows June 2023 or later date in Settings > About phone > Android version.📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs
- SELinux denials related to PowerVR driver
- Unexpected privilege escalation attempts
Network Indicators:
- None - this is a local vulnerability
SIEM Query:
source="android" AND (event_type="kernel_panic" OR process_name="pvr" OR privilege_escalation=true)