CVE-2021-35103
📋 TL;DR
This vulnerability allows an attacker to write data beyond allocated memory bounds in Qualcomm Snapdragon chipsets due to improper validation of timer values from firmware. It affects multiple Snapdragon platforms including automotive, mobile, wearables, and networking devices. Successful exploitation could lead to arbitrary code execution or system crashes.
💻 Affected Systems
- Snapdragon Auto
- Snapdragon Compute
- Snapdragon Connectivity
- Snapdragon Industrial IOT
- Snapdragon Mobile
- Snapdragon Wearables
- Snapdragon Wired Infrastructure and Networking
📦 What is this software?
⚠️ 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
System instability, crashes, or denial of service affecting device functionality.
If Mitigated
Limited impact with proper memory protection mechanisms and firmware validation in place.
🎯 Exploit Status
Exploitation requires firmware-level access or ability to manipulate timer synchronization. No public exploits known as of bulletin date.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Firmware updates released in March 2022 security bulletin
Vendor Advisory: https://www.qualcomm.com/company/product-security/bulletins/march-2022-bulletin
Restart Required: Yes
Instructions:
1. Contact device manufacturer for firmware updates. 2. Apply Qualcomm-provided firmware patches. 3. Reboot device after update. 4. Verify patch installation through version checks.
🔧 Temporary Workarounds
Firmware Validation Enhancement
allImplement additional validation of timer values in firmware synchronization routines
Memory Protection
allEnable hardware memory protection features if available on chipset
🧯 If You Can't Patch
- Isolate affected devices from untrusted networks
- Implement strict firmware update controls and validation
🔍 How to Verify
Check if Vulnerable:
Check device chipset model and firmware version against Qualcomm's March 2022 security bulletinCheck Version:
Device-specific commands vary by manufacturer; typically 'cat /proc/version' or manufacturer-specific firmware check utilitiesVerify Fix Applied:
Verify firmware version has been updated to post-March 2022 release📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs
- Memory corruption errors
- Firmware synchronization failures
Network Indicators:
- Unexpected firmware update attempts
- Anomalous timer synchronization traffic
SIEM Query:
Search for kernel panic events OR memory corruption errors in device logs