CVE-2023-21065
📋 TL;DR
This CVE describes an integer overflow vulnerability in Android's fdt.c that could allow local privilege escalation. An attacker could exploit this to gain elevated system privileges on affected Android devices. Only Android devices with vulnerable kernel versions are affected.
💻 Affected Systems
- Android
📦 What is this software?
Android by Google
⚠️ Risk & Real-World Impact
Worst Case
Full device compromise with kernel-level access, allowing complete control over the Android system and all user data.
Likely Case
Local privilege escalation where a malicious app could gain system-level permissions to access sensitive data or install persistent malware.
If Mitigated
Limited impact if devices are patched or have proper app sandboxing and SELinux policies enforced.
🎯 Exploit Status
Exploitation requires local access and system execution privileges. No user interaction needed once initial access is obtained.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: March 2023 Android Security Bulletin patches
Vendor Advisory: https://source.android.com/security/bulletin/pixel/2023-03-01
Restart Required: Yes
Instructions:
1. Apply March 2023 Android Security Update via Settings > System > System Update. 2. For Pixel devices, ensure build number TQ2A.230305.008.C1 or later. 3. For other Android devices, check manufacturer's security update schedule.
🔧 Temporary Workarounds
Restrict app permissions
androidLimit app permissions to reduce attack surface for potential malicious apps
Enable Google Play Protect
androidEnsure Google Play Protect is enabled to detect potentially harmful apps
🧯 If You Can't Patch
- Restrict installation of apps from unknown sources
- Implement mobile device management (MDM) policies to control app installations
🔍 How to Verify
Check if Vulnerable:
Check Android security patch level in Settings > About phone > Android version. If patch level is earlier than March 2023, device is vulnerable.Check Version:
adb shell getprop ro.build.version.security_patchVerify Fix Applied:
Verify security patch level shows 'March 5, 2023' or later in Settings > About phone > Android version.📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs
- SELinux denials related to fdt operations
- Abnormal privilege escalation attempts
Network Indicators:
- None - this is a local vulnerability
SIEM Query:
source="android_kernel" AND (event="kernel_panic" OR event="oops") AND message="*fdt*"