CVE-2021-30289
📋 TL;DR
This vulnerability allows attackers to execute arbitrary code or cause denial of service via buffer overflow in Qualcomm Snapdragon chipsets. It affects devices using Snapdragon Auto, Compute, Consumer IOT, Industrial IOT, Mobile, Voice & Music, and Wearables platforms. Attackers can exploit this by sending specially crafted DIAG commands for COEX management.
💻 Affected Systems
- Snapdragon Auto
- Snapdragon Compute
- Snapdragon Consumer IOT
- Snapdragon Industrial IOT
- Snapdragon Mobile
- Snapdragon Voice & Music
- Snapdragon Wearables
📦 What is this software?
Sd7c Firmware by Qualcomm
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution with kernel privileges leading to complete device compromise, data theft, or persistent backdoor installation.
Likely Case
Denial of service causing device crashes or instability, potentially requiring physical reset.
If Mitigated
Limited impact if proper input validation and memory protections are implemented at system level.
🎯 Exploit Status
Exploitation requires access to DIAG interface and knowledge of COEX management protocol. No public exploits known as of December 2021 bulletin.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Refer to Qualcomm security bulletin for specific chipset versions
Vendor Advisory: https://www.qualcomm.com/company/product-security/bulletins/december-2021-bulletin
Restart Required: Yes
Instructions:
1. Contact device manufacturer for firmware updates. 2. Apply Qualcomm-provided patches through OEM channels. 3. Update device firmware to latest secure version. 4. Reboot device after update.
🔧 Temporary Workarounds
Disable DIAG interface
allDisable diagnostic interfaces if not required for operations
Device-specific - consult manufacturer documentation
Network segmentation
allIsolate devices with DIAG interfaces from untrusted networks
🧯 If You Can't Patch
- Implement strict network access controls to DIAG interfaces
- Monitor for abnormal DIAG command patterns and device crashes
🔍 How to Verify
Check if Vulnerable:
Check device chipset model and firmware version against Qualcomm advisory. Use 'getprop ro.bootloader' or similar on Android devices.Check Version:
Android: 'getprop ro.build.version.security_patch' or 'cat /proc/version'. Embedded: manufacturer-specific commands.Verify Fix Applied:
Verify firmware version has been updated to patched version from manufacturer. Check for December 2021 or later security patches.📡 Detection & Monitoring
Log Indicators:
- Unexpected device reboots
- Kernel panic logs
- DIAG interface access from unusual sources
Network Indicators:
- Unusual traffic to DIAG ports (typically 6666-6669)
- Malformed COEX management packets
SIEM Query:
source_port IN (6666,6667,6668,6669) AND payload_contains("COEX")