CVE-2021-1937
📋 TL;DR
This vulnerability in Qualcomm Snapdragon chipsets allows an attacker to trigger a reachable assertion while processing WLAN peer association messages, potentially causing denial of service or remote code execution. It affects numerous Snapdragon product lines including Auto, Compute, Mobile, and Industrial IoT devices. The vulnerability requires sending specially crafted network packets to vulnerable devices.
💻 Affected Systems
- Snapdragon Auto
- Snapdragon Compute
- Snapdragon Connectivity
- Snapdragon Consumer Electronics Connectivity
- Snapdragon Consumer IOT
- Snapdragon Industrial IOT
- Snapdragon Mobile
- Snapdragon Voice & Music
- Snapdragon Wired Infrastructure and Networking
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete device compromise, allowing attacker to execute arbitrary code with system privileges.
Likely Case
Denial of service causing device crashes or instability in WLAN functionality, disrupting network connectivity.
If Mitigated
Limited impact with proper network segmentation and firewall rules blocking malicious WLAN traffic.
🎯 Exploit Status
Exploitation requires sending specially crafted WLAN packets to vulnerable devices. No public exploit code has been released as of the advisory date.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Varies by device manufacturer - check with OEM for specific firmware updates
Vendor Advisory: https://www.qualcomm.com/company/product-security/bulletins/june-2021-bulletin
Restart Required: Yes
Instructions:
1. Check with device manufacturer for firmware updates. 2. Apply the firmware update provided by the OEM. 3. Reboot the device to complete the update. 4. Verify the patch is applied successfully.
🔧 Temporary Workarounds
Network Segmentation
allIsolate vulnerable devices on separate network segments to limit attack surface
WLAN Access Control
allImplement strict WLAN access controls and authentication to prevent unauthorized devices from connecting
🧯 If You Can't Patch
- Implement network monitoring for unusual WLAN traffic patterns
- Consider disabling WLAN functionality if not required for device operation
🔍 How to Verify
Check if Vulnerable:
Check device specifications against affected Snapdragon chipsets and firmware version against OEM security updatesCheck Version:
Device-specific commands vary by manufacturer (e.g., 'cat /proc/version' on Linux-based systems)Verify Fix Applied:
Verify firmware version matches or exceeds the patched version provided by device manufacturer📡 Detection & Monitoring
Log Indicators:
- Unexpected device crashes or reboots
- WLAN driver/interface errors in system logs
- Failed association attempts with unusual parameters
Network Indicators:
- Unusual WLAN traffic patterns
- Malformed WLAN association packets
- Traffic from unauthorized MAC addresses
SIEM Query:
Search for WLAN interface errors, device crash reports, or failed association attempts in system logs