CVE-2021-0925
📋 TL;DR
This vulnerability allows remote attackers to read memory beyond intended boundaries in Android's NFC Type 4 Tag processing code. It could lead to information disclosure without requiring user interaction or additional privileges. Only Android 12 devices are affected.
💻 Affected Systems
- Android
📦 What is this software?
Android by Google
⚠️ Risk & Real-World Impact
Worst Case
Remote attacker could read sensitive memory contents from the Android device, potentially exposing cryptographic keys, authentication tokens, or other protected data.
Likely Case
Limited information disclosure where attacker can read some out-of-bounds memory but cannot control what data is leaked.
If Mitigated
No impact if patched; otherwise, information disclosure limited to NFC-related memory regions.
🎯 Exploit Status
Exploitation requires physical proximity for NFC communication and understanding of NFC Type 4 Tag protocol.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Android Security Patch Level 2021-11-01 or later
Vendor Advisory: https://source.android.com/security/bulletin/2021-11-01
Restart Required: Yes
Instructions:
1. Check for Android system updates in Settings > System > System update. 2. Install Android Security Patch Level 2021-11-01 or later. 3. Reboot device after installation.
🔧 Temporary Workarounds
Disable NFC
androidTurn off NFC functionality to prevent exploitation
Settings > Connected devices > Connection preferences > NFC > Toggle OFF
🧯 If You Can't Patch
- Disable NFC functionality completely
- Restrict physical access to devices and implement NFC usage policies
🔍 How to Verify
Check if Vulnerable:
Check Android version: Settings > About phone > Android version. If Android 12 and Security Patch Level earlier than 2021-11-01, device is vulnerable.Check Version:
adb shell getprop ro.build.version.security_patchVerify Fix Applied:
Verify Android Security Patch Level is 2021-11-01 or later: Settings > About phone > Android Security Patch Level.📡 Detection & Monitoring
Log Indicators:
- Unusual NFC activity logs, system crashes in NFC service
Network Indicators:
- N/A - This is a local NFC-based vulnerability
SIEM Query:
N/A - Physical proximity attack not detectable via network monitoring