CVE-2021-37020
📋 TL;DR
This CVE describes a stack-based buffer overflow vulnerability in Huawei smartphones running HarmonyOS. Successful exploitation could allow attackers to execute arbitrary code or cause denial of service through out-of-bounds memory reads. The vulnerability affects Huawei smartphone users with unpatched devices.
💻 Affected Systems
- Huawei smartphones running HarmonyOS
📦 What is this software?
Emui by Huawei
Emui by Huawei
Emui by Huawei
Emui by Huawei
Emui by Huawei
Emui by Huawei
Harmonyos by Huawei
Magic Ui by Huawei
Magic Ui by Huawei
Magic Ui by Huawei
Magic Ui by Huawei
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete device compromise, data theft, or persistent backdoor installation.
Likely Case
Application crashes, denial of service, or limited information disclosure through memory leaks.
If Mitigated
No impact if patched; limited impact if exploit attempts are blocked by security controls.
🎯 Exploit Status
Buffer overflow vulnerabilities typically require specific conditions to exploit; no public exploit code is documented.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: September 2021 HarmonyOS security update
Vendor Advisory: https://device.harmonyos.com/en/docs/security/update/security-bulletins-202109-0000001196270727
Restart Required: Yes
Instructions:
1. Navigate to Settings > System & updates > Software update on the Huawei device. 2. Check for and install the September 2021 security update. 3. Restart the device after installation completes.
🧯 If You Can't Patch
- Disable unnecessary applications and services to reduce attack surface.
- Implement network segmentation to limit device exposure to untrusted networks.
🔍 How to Verify
Check if Vulnerable:
Check the HarmonyOS version in Settings > About phone > HarmonyOS version; if before September 2021 update, device is vulnerable.Check Version:
Not applicable for mobile devices; use GUI settings as above.Verify Fix Applied:
Verify the installed security update includes September 2021 patches via Settings > System & updates > Software update > Update history.📡 Detection & Monitoring
Log Indicators:
- Unexpected application crashes, memory access violations in system logs.
Network Indicators:
- Unusual network traffic from the device to unknown destinations.
SIEM Query:
Not typically applicable for mobile devices; monitor for anomaly alerts from mobile device management (MDM) solutions.