CVE-2023-21353
📋 TL;DR
CVE-2023-21353 is an out-of-bounds read vulnerability in Android's NFC stack (NFA) that allows remote attackers to read memory contents without authentication or user interaction. This could lead to information disclosure of sensitive data. All Android devices with vulnerable NFC implementations are affected.
💻 Affected Systems
- Android devices with NFC capability
📦 What is this software?
Android by Google
⚠️ Risk & Real-World Impact
Worst Case
Remote attacker could read sensitive memory contents including authentication tokens, encryption keys, or other protected data from the device without any user interaction.
Likely Case
Information disclosure of limited memory regions, potentially exposing device identifiers, temporary data, or application information.
If Mitigated
With proper network segmentation and NFC disabled, impact is minimal as exploitation requires NFC communication capability.
🎯 Exploit Status
Exploitation requires physical proximity to target device and specialized NFC equipment. No authentication or user interaction needed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Android 14 (API level 34) and later
Vendor Advisory: https://source.android.com/docs/security/bulletin/android-14
Restart Required: Yes
Instructions:
1. Update device to Android 14 or later. 2. For devices not receiving Android 14 updates, check with device manufacturer for security patches. 3. Apply any available security updates through Settings > System > System update.
🔧 Temporary Workarounds
Disable NFC functionality
androidTurn off NFC to prevent exploitation via this vector
Settings > Connected devices > Connection preferences > NFC > Toggle OFF
🧯 If You Can't Patch
- Disable NFC functionality on all vulnerable devices
- Implement physical security controls to prevent unauthorized NFC device proximity
🔍 How to Verify
Check if Vulnerable:
Check Android version: Settings > About phone > Android version. If version is below Android 14, device is potentially vulnerable if it has NFC hardware.Check Version:
adb shell getprop ro.build.version.releaseVerify Fix Applied:
Verify Android version is 14 or higher: Settings > About phone > Android version should show 14 or higher.📡 Detection & Monitoring
Log Indicators:
- Unusual NFC activity logs
- NFC stack crash logs
- System logs showing NFC service errors
Network Indicators:
- N/A - This is a local NFC vulnerability, not network-based
SIEM Query:
N/A - Physical proximity attack not detectable via network monitoring