CVE-2020-3703
📋 TL;DR
This CVE describes a buffer over-read vulnerability in Bluetooth peripheral firmware across multiple Qualcomm Snapdragon platforms. Attackers can exploit this by sending specially crafted Bluetooth packets with invalid opcodes or lengths, potentially leading to information disclosure or remote code execution. The vulnerability affects a wide range of Qualcomm-based devices including automotive, mobile, IoT, and compute platforms.
💻 Affected Systems
- Snapdragon Auto
- Snapdragon Compute
- Snapdragon Connectivity
- Snapdragon Consumer Electronics Connectivity
- Snapdragon Consumer IOT
- Snapdragon Industrial IOT
- Snapdragon IoT
- Snapdragon Mobile
- Snapdragon Voice & Music
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete device compromise, data theft, and persistent access to affected systems.
Likely Case
Information disclosure through memory leaks, potential denial of service, or limited code execution depending on Bluetooth stack implementation.
If Mitigated
Limited impact if Bluetooth is disabled or devices are not within attacker proximity, though the vulnerability is remotely exploitable via Bluetooth.
🎯 Exploit Status
Related to SweynTooth vulnerabilities (CVE-2019-16336, CVE-2019-17518, CVE-2019-17519) with known exploitation techniques. Attack requires proximity to target device.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Vendor-specific firmware updates
Vendor Advisory: https://www.qualcomm.com/company/product-security/bulletins/october-2020-bulletin
Restart Required: Yes
Instructions:
1. Check with device manufacturer for firmware updates. 2. Apply Qualcomm-provided patches through OEM update channels. 3. Reboot device after update. 4. Verify Bluetooth functionality post-update.
🔧 Temporary Workarounds
Disable Bluetooth
allTurn off Bluetooth functionality to prevent exploitation
adb shell settings put global bluetooth_on 0
systemctl stop bluetooth
rfkill block bluetooth
Restrict Bluetooth Visibility
linuxSet Bluetooth to non-discoverable mode to reduce attack surface
hciconfig hci0 noscan
bluetoothctl discoverable off
🧯 If You Can't Patch
- Segment network to isolate Bluetooth-enabled devices
- Implement physical security controls to limit Bluetooth proximity access
🔍 How to Verify
Check if Vulnerable:
Check device chipset model and firmware version against Qualcomm advisory. Use commands like 'cat /proc/cpuinfo' or device-specific firmware version checks.Check Version:
Device-specific commands vary by manufacturer. Common examples: 'getprop ro.build.fingerprint' (Android) or checking firmware version in device settings.Verify Fix Applied:
Verify firmware version has been updated to post-October 2020 patches. Check with device manufacturer for specific patch verification procedures.📡 Detection & Monitoring
Log Indicators:
- Bluetooth stack crashes
- Memory access violations in Bluetooth logs
- Unusual Bluetooth connection attempts
Network Indicators:
- Malformed Bluetooth packets
- Unexpected Bluetooth pairing requests
- Abnormal Bluetooth traffic patterns
SIEM Query:
source="bluetooth_logs" AND (event="crash" OR event="memory_violation" OR packet_length>expected_value)