CVE-2020-11243
📋 TL;DR
This vulnerability in Qualcomm Snapdragon chipsets allows denial of service attacks when the Radio Resource Control (RRC) incorrectly signals connection establishment success despite validation failures. This affects devices using vulnerable Snapdragon Auto, Compute, Connectivity, and Mobile chipsets, potentially causing service disruption.
💻 Affected Systems
- Snapdragon Auto
- Snapdragon Compute
- Snapdragon Connectivity
- Snapdragon Mobile
📦 What is this software?
Sd8c Firmware by Qualcomm
⚠️ Risk & Real-World Impact
Worst Case
Complete denial of service on affected devices, rendering them unable to establish network connections or requiring device restart.
Likely Case
Intermittent service disruption or connection failures on affected devices during specific network handshake scenarios.
If Mitigated
Minimal impact if patched; unpatched devices remain vulnerable to targeted attacks.
🎯 Exploit Status
Exploitation requires specific network conditions to trigger the RRC validation failure scenario.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Refer to Qualcomm April 2021 security bulletin for specific patched versions
Vendor Advisory: https://www.qualcomm.com/company/product-security/bulletins/april-2021-bulletin
Restart Required: Yes
Instructions:
1. Check device manufacturer for firmware updates. 2. Apply Qualcomm-provided patches through device firmware updates. 3. Reboot device after update.
🔧 Temporary Workarounds
Network segmentation
allIsolate vulnerable devices from untrusted networks to reduce attack surface
🧯 If You Can't Patch
- Monitor network traffic for abnormal connection establishment patterns
- Implement strict network access controls for affected devices
🔍 How to Verify
Check if Vulnerable:
Check device chipset version and compare against Qualcomm's affected list in April 2021 bulletinCheck Version:
Device-specific commands vary; typically check in device settings or use manufacturer diagnostic toolsVerify Fix Applied:
Verify firmware version has been updated to post-April 2021 release from device manufacturer📡 Detection & Monitoring
Log Indicators:
- Multiple RRC connection establishment failures followed by success signals
- Unexpected device reboots or network disconnections
Network Indicators:
- Abnormal RRC signaling patterns
- Repeated connection setup attempts
SIEM Query:
Search for RRC protocol anomalies or device disconnection events in network logs