CVE-2023-20977
📋 TL;DR
This CVE describes an out-of-bounds read vulnerability in Android's Bluetooth Low Energy (BLE) stack that could allow local information disclosure. It affects Android 13 devices and requires system-level privileges for exploitation, meaning an attacker would need to already have compromised the device's firmware.
💻 Affected Systems
- Android
📦 What is this software?
Android by Google
⚠️ Risk & Real-World Impact
Worst Case
An attacker with system privileges could read sensitive memory contents from the Bluetooth stack, potentially exposing cryptographic keys, device identifiers, or other protected information.
Likely Case
Limited information disclosure from Bluetooth-related memory regions, potentially exposing device-specific Bluetooth configuration data.
If Mitigated
No impact if system is not already compromised, as exploitation requires system execution privileges.
🎯 Exploit Status
Exploitation requires system privileges and knowledge of Bluetooth stack internals. No public exploits known.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Android Security Update June 2023 or later
Vendor Advisory: https://source.android.com/security/bulletin/pixel/2023-06-01
Restart Required: Yes
Instructions:
1. Check for Android system updates in Settings > System > System update. 2. Install the June 2023 or later security update. 3. Reboot device after installation.
🔧 Temporary Workarounds
Disable Bluetooth when not in use
androidReduces attack surface by disabling Bluetooth functionality
adb shell settings put global bluetooth_on 0
🧯 If You Can't Patch
- Restrict Bluetooth permissions to essential apps only
- Monitor for unusual Bluetooth activity or privilege escalation attempts
🔍 How to Verify
Check if Vulnerable:
Check Android version: Settings > About phone > Android version. If it shows Android 13 without June 2023 security patch, device is vulnerable.Check Version:
adb shell getprop ro.build.version.release && adb shell getprop ro.build.version.security_patchVerify Fix Applied:
Verify Android Security Patch Level is June 2023 or later: Settings > About phone > Android Security Update.📡 Detection & Monitoring
Log Indicators:
- Unusual Bluetooth stack crashes or memory access errors in system logs
- Privilege escalation attempts involving Bluetooth services
Network Indicators:
- None - this is a local vulnerability
SIEM Query:
source="android_system" AND ("btm_ble" OR "Bluetooth stack" OR "CVE-2023-20977")