CVE-2023-21250
📋 TL;DR
This is a critical Bluetooth stack vulnerability in Android's GATT implementation that allows remote code execution without user interaction. Attackers can exploit this by sending specially crafted Bluetooth packets to vulnerable devices, potentially taking full control of affected Android devices.
💻 Affected Systems
- Android devices with Bluetooth functionality
📦 What is this software?
Android by Google
Android by Google
Android by Google
Android by Google
⚠️ Risk & Real-World Impact
Worst Case
Full device compromise leading to data theft, surveillance, ransomware deployment, or use as a botnet node
Likely Case
Remote code execution allowing attacker to install malware, steal sensitive data, or gain persistent access
If Mitigated
Limited impact if Bluetooth is disabled or device is patched, though initial exploitation could still occur
🎯 Exploit Status
No authentication required, no user interaction needed. Exploitation requires proximity or ability to send Bluetooth packets to target device.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: July 2023 Android Security Patch or later
Vendor Advisory: https://source.android.com/security/bulletin/2023-07-01
Restart Required: Yes
Instructions:
1. Check for Android system updates in Settings > System > System Update. 2. Install July 2023 or later security patch. 3. Reboot device after installation.
🔧 Temporary Workarounds
Disable Bluetooth
androidTurn off Bluetooth functionality to prevent exploitation
Settings > Connected devices > Connection preferences > Bluetooth > Toggle off
Restrict Bluetooth Visibility
androidSet Bluetooth to non-discoverable mode to reduce attack surface
Settings > Connected devices > Connection preferences > Bluetooth > Device name > Turn off 'Make device discoverable'
🧯 If You Can't Patch
- Disable Bluetooth completely when not in use
- Implement network segmentation to isolate vulnerable devices from critical systems
🔍 How to Verify
Check if Vulnerable:
Check Android security patch level in Settings > About phone > Android version > Security patch levelCheck Version:
adb shell getprop ro.build.version.security_patchVerify Fix Applied:
Verify security patch level shows 'July 5, 2023' or later date📡 Detection & Monitoring
Log Indicators:
- Unusual Bluetooth connection attempts, crashes in Bluetooth service (logcat)
Network Indicators:
- Suspicious Bluetooth packet patterns, unexpected Bluetooth connections
SIEM Query:
source="android_logs" AND (process="bluetooth" OR process="com.android.bluetooth") AND (message="*crash*" OR message="*segfault*" OR message="*out of bounds*")🔗 References
- https://android.googlesource.com/platform/packages/modules/Bluetooth/+/ec573bc83f1ed6722f7cb29431dcb2db7f10bf28
- https://source.android.com/security/bulletin/2023-07-01
- https://android.googlesource.com/platform/packages/modules/Bluetooth/+/ec573bc83f1ed6722f7cb29431dcb2db7f10bf28
- https://source.android.com/security/bulletin/2023-07-01
