CVE-2021-0874
📋 TL;DR
This CVE describes an integer overflow vulnerability in the PowerVR kernel driver on Android devices. It allows local attackers to gain escalated privileges without user interaction by exploiting missing size checks that lead to out-of-bounds heap access. This 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
Full device compromise with kernel-level access, allowing installation of persistent malware, data theft, and complete system control.
Likely Case
Local privilege escalation enabling attackers to bypass security restrictions, access sensitive data, and install malicious applications.
If Mitigated
Limited impact with proper patch management and security controls in place, though still a serious local vulnerability.
🎯 Exploit Status
Requires local access and knowledge of kernel memory layout. No user interaction needed for exploitation.
🛠️ 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. Apply Android security updates from April 2023 or later. 2. Update device firmware through manufacturer channels. 3. Reboot device after update installation.
🔧 Temporary Workarounds
Restrict local app installation
androidLimit installation of untrusted applications to reduce attack surface
adb shell settings put secure install_non_market_apps 0
🧯 If You Can't Patch
- Isolate affected devices from sensitive networks and data
- Implement strict application whitelisting and monitoring
🔍 How to Verify
Check if Vulnerable:
Check Android security patch level (Settings > About phone > Android security patch level) - if before April 2023, likely vulnerableCheck Version:
adb shell getprop ro.build.version.security_patchVerify Fix Applied:
Verify Android security patch level is April 2023 or later📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs
- Unusual privilege escalation attempts in system logs
- SELinux/AppArmor denials related to PowerVR driver
Network Indicators:
- Not applicable - local vulnerability
SIEM Query:
source="android_system" AND ("PowerVR" OR "PVRSRV" OR "kernel panic")