CVE-2021-0872
📋 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 PowerVR graphics hardware.
💻 Affected Systems
- Android devices with PowerVR graphics hardware
📦 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 bypass app sandboxing, access sensitive data, and install malicious apps with elevated permissions.
If Mitigated
Limited impact if SELinux policies restrict kernel access or if the vulnerable driver is not loaded/used.
🎯 Exploit Status
Requires local access to device. No public exploit code available as of knowledge cutoff.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: April 2023 Android Security Bulletin
Vendor Advisory: https://source.android.com/security/bulletin/2023-04-01
Restart Required: Yes
Instructions:
1. Check for Android system updates in Settings > System > System update. 2. Install April 2023 or later security patch. 3. Reboot device after installation.
🔧 Temporary Workarounds
Disable PowerVR driver (if possible)
linuxPrevent loading of vulnerable kernel module
echo 'blacklist pvrsrvkm' >> /etc/modprobe.d/blacklist.conf
rmmod pvrsrvkm
🧯 If You Can't Patch
- Restrict physical access to devices and implement strong device management policies
- Use Android Enterprise or MDM solutions 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 April 2023, device is vulnerable if it has PowerVR GPU.Check Version:
adb shell getprop ro.build.version.security_patchVerify Fix Applied:
Verify security patch level shows April 2023 or later 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 exploit
SIEM Query:
source="android_kernel" AND ("pvrsrv" OR "PowerVR") AND ("overflow" OR "OOB" OR "privilege escalation")