CVE-2021-37120
📋 TL;DR
CVE-2021-37120 is a double-free vulnerability in Huawei smartphones that allows attackers to cause kernel crashes or potentially escalate privileges. This affects Huawei smartphone users running vulnerable software versions. The vulnerability occurs when memory is freed twice, leading to memory corruption.
💻 Affected Systems
- Huawei smartphones
📦 What is this software?
Emui by Huawei
Emui by Huawei
Magic Ui by Huawei
Magic Ui by Huawei
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise with kernel-level privilege escalation, allowing attackers to execute arbitrary code with highest system privileges.
Likely Case
Device instability, kernel crashes leading to denial of service, or limited privilege escalation in constrained scenarios.
If Mitigated
Reduced impact through security controls like exploit mitigations, but still potential for denial of service.
🎯 Exploit Status
Exploitation typically requires local access or ability to execute code on the device. Double-free vulnerabilities can be complex to exploit reliably.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Huawei security bulletins for specific patched versions
Vendor Advisory: https://consumer.huawei.com/en/support/bulletin/2021/10/
Restart Required: Yes
Instructions:
1. Check for system updates in device settings. 2. Install latest security update from Huawei. 3. Reboot device after update completes.
🔧 Temporary Workarounds
Avoid untrusted apps
allPrevent installation of applications from untrusted sources to reduce attack surface.
Enable security features
allEnsure all device security features are enabled including app verification and security scanning.
🧯 If You Can't Patch
- Restrict device to essential applications only from trusted sources
- Implement mobile device management with strict application control policies
🔍 How to Verify
Check if Vulnerable:
Check device security patch level in Settings > About phone > Build number and compare with Huawei security bulletins.Check Version:
No single command; check via device Settings > About phoneVerify Fix Applied:
Verify security patch date is October 2021 or later in device settings after update.📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs
- Unexpected process crashes
- Memory corruption errors in system logs
Network Indicators:
- Unusual outbound connections from system processes
SIEM Query:
Device logs showing kernel crashes or privilege escalation attempts from userland processes