CVE-2021-30336
📋 TL;DR
This vulnerability allows attackers to read memory outside the intended buffer bounds when processing APK close session requests in Qualcomm Snapdragon chipsets. It affects devices using Snapdragon Auto, Compute, Connectivity, Industrial IoT, and Wearables platforms. Successful exploitation could lead to information disclosure or system compromise.
💻 Affected Systems
- Snapdragon Auto
- Snapdragon Compute
- Snapdragon Connectivity
- Snapdragon Industrial IOT
- Snapdragon Wearables
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete device compromise, data theft, or persistent backdoor installation.
Likely Case
Information disclosure through memory read, potentially exposing sensitive data or cryptographic keys.
If Mitigated
Limited impact with proper memory protection mechanisms and input validation in place.
🎯 Exploit Status
Requires sending specially crafted APK close session requests to trigger the out-of-bounds read
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Refer to Qualcomm December 2021 security bulletin for specific chipset updates
Vendor Advisory: https://www.qualcomm.com/company/product-security/bulletins/december-2021-bulletin
Restart Required: Yes
Instructions:
1. Check device manufacturer for firmware updates. 2. Apply Qualcomm-provided patches through OEM updates. 3. Reboot device after update installation.
🔧 Temporary Workarounds
Network segmentation
allIsolate affected devices from untrusted networks to limit attack surface
Input validation at application layer
allImplement additional validation for APK session handling in applications
🧯 If You Can't Patch
- Implement strict network access controls to limit who can communicate with affected devices
- Monitor for abnormal APK session termination patterns in network traffic
🔍 How to Verify
Check if Vulnerable:
Check device chipset version and compare against Qualcomm's patched versions in December 2021 bulletinCheck Version:
Device-specific commands vary by manufacturer; typically 'getprop ro.build.fingerprint' or similar on Android devicesVerify Fix Applied:
Verify firmware version has been updated to include December 2021 Qualcomm security patches📡 Detection & Monitoring
Log Indicators:
- Unusual APK session termination patterns
- Memory access violation logs in system logs
Network Indicators:
- Abnormal APK close session requests to Snapdragon services
- Unexpected network traffic to chipset management interfaces
SIEM Query:
Search for APK session termination events with abnormal parameters or timing patterns