CVE-2021-39978
📋 TL;DR
This CVE describes a SQL injection vulnerability in a telephony application that allows attackers to execute arbitrary SQL commands. Successful exploitation could lead to unauthorized data access, modification, or deletion. This affects users of vulnerable telephony applications on HarmonyOS devices.
💻 Affected Systems
- HarmonyOS Telephony Application
📦 What is this software?
Harmonyos by Huawei
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of telephony database including call logs, contacts, messages, and potentially device control through privilege escalation.
Likely Case
Unauthorized access to sensitive telephony data including call history, contacts, and messages, potentially leading to privacy violations.
If Mitigated
Limited impact with proper input validation and database permissions in place, potentially only allowing read-only access to non-sensitive data.
🎯 Exploit Status
SQL injection typically requires some level of user interaction or specific conditions; complexity depends on input validation mechanisms.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Refer to October 2021 HarmonyOS security updates
Vendor Advisory: https://device.harmonyos.com/en/docs/security/update/security-bulletins-202110-0000001162998526
Restart Required: Yes
Instructions:
1. Check for HarmonyOS system updates in device settings. 2. Apply the October 2021 security update. 3. Restart device after update installation.
🔧 Temporary Workarounds
Disable vulnerable telephony features
allTemporarily disable or restrict telephony application features that accept user input until patched
Network segmentation
allIsolate affected devices from critical networks to limit potential data exfiltration
🧯 If You Can't Patch
- Implement strict input validation and parameterized queries at application level
- Apply network controls to limit database access and monitor for suspicious SQL queries
🔍 How to Verify
Check if Vulnerable:
Check HarmonyOS version and verify if October 2021 security updates have been appliedCheck Version:
Settings > About phone > HarmonyOS versionVerify Fix Applied:
Confirm installation of October 2021 HarmonyOS security updates and test telephony application functionality📡 Detection & Monitoring
Log Indicators:
- Unusual SQL query patterns in telephony application logs
- Multiple failed login or query attempts
Network Indicators:
- Unexpected database connections from telephony application
- Suspicious outbound data transfers
SIEM Query:
source="telephony_app" AND (query="SELECT" OR query="INSERT" OR query="UPDATE") AND user_input="*"