CVE-2021-22389
📋 TL;DR
This is a critical permission control vulnerability in Huawei smartphones that allows attackers to bypass security restrictions and execute arbitrary code. It affects multiple Huawei smartphone models running specific EMUI versions. Successful exploitation could lead to complete device compromise.
💻 Affected Systems
- Huawei smartphones
📦 What is this software?
Emui by Huawei
Magic Ui by Huawei
⚠️ Risk & Real-World Impact
Worst Case
Complete device takeover with root/system privileges, allowing data theft, surveillance, and persistent backdoor installation
Likely Case
Local privilege escalation leading to unauthorized access to sensitive data and system functions
If Mitigated
Limited impact with proper app sandboxing and security controls in place
🎯 Exploit Status
Requires local access or malicious app installation; no public exploit code available
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: EMUI 11.0.1.166 and later, Magic UI 4.0.1.166 and later
Vendor Advisory: https://consumer.huawei.com/en/support/bulletin/2021/6/
Restart Required: Yes
Instructions:
1. Check for system updates in Settings > System & updates > Software update. 2. Download and install the latest security update. 3. Restart device after installation completes.
🔧 Temporary Workarounds
Disable unknown sources
androidPrevent installation of malicious apps from unknown sources
Settings > Security > Install unknown apps > Disable for all apps
Enable Google Play Protect
androidUse built-in malware scanning for installed apps
Google Play Store > Menu > Play Protect > Scan device for security threats
🧯 If You Can't Patch
- Restrict physical access to devices and implement mobile device management (MDM) controls
- Monitor for suspicious app installations and unusual device behavior
🔍 How to Verify
Check if Vulnerable:
Check EMUI/Magic UI version in Settings > About phone > EMUI version/Magic UI versionCheck Version:
Settings > About phone > EMUI version/Magic UI versionVerify Fix Applied:
Verify version is EMUI 11.0.1.166+ or Magic UI 4.0.1.166+ after update📡 Detection & Monitoring
Log Indicators:
- Unusual permission requests in app logs
- Suspicious system service activations
Network Indicators:
- Unexpected outbound connections from system processes
SIEM Query:
Device logs showing privilege escalation attempts or unusual permission grants