CVE-2020-11831
📋 TL;DR
CVE-2020-11831 is a critical vulnerability in OvoiceManager that allows arbitrary file writes due to improper system permissions. Attackers can exploit this to overwrite system files, potentially leading to privilege escalation or system compromise. This affects OPPO devices running com.oppo.ovoicemanager version 2.0.1.
💻 Affected Systems
- OvoiceManager (com.oppo.ovoicemanager)
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise through privilege escalation to root/system level, allowing installation of persistent malware, data theft, or device bricking.
Likely Case
Local privilege escalation allowing attackers to gain elevated permissions and access sensitive data or install unwanted applications.
If Mitigated
Limited impact if proper application sandboxing and permission controls are enforced, restricting file write operations to designated directories.
🎯 Exploit Status
Exploitation requires local access to the device, likely through a malicious application or physical access. The vulnerability involves abusing system permissions rather than complex code execution.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Later versions than V2.0.1 (specific version not specified in references)
Vendor Advisory: https://security.oppo.com/en/noticedetails.html?noticeId=NOTICE-1328876061836189696
Restart Required: Yes
Instructions:
1. Check for system updates in device settings. 2. Install the latest OTA update from OPPO. 3. Ensure OvoiceManager is updated through the app store if available. 4. Restart the device after update.
🔧 Temporary Workarounds
Disable or remove OvoiceManager
androidTemporarily disable or uninstall the vulnerable application to prevent exploitation.
adb shell pm disable-user com.oppo.ovoicemanager
adb uninstall com.oppo.ovoicemanager
Restrict application permissions
androidRevoke unnecessary system permissions from OvoiceManager through device settings.
🧯 If You Can't Patch
- Isolate affected devices from sensitive networks and data.
- Implement strict application whitelisting to prevent installation of malicious apps that could exploit this vulnerability.
🔍 How to Verify
Check if Vulnerable:
Check OvoiceManager version in device settings > Apps > OvoiceManager > App info, or use: adb shell dumpsys package com.oppo.ovoicemanager | grep versionNameCheck Version:
adb shell dumpsys package com.oppo.ovoicemanager | grep versionNameVerify Fix Applied:
Verify OvoiceManager version is updated beyond V2.0.1 and check for absence of arbitrary file write permissions in app settings.📡 Detection & Monitoring
Log Indicators:
- Unusual file write operations by OvoiceManager to system directories
- Permission escalation attempts in system logs
Network Indicators:
- Not applicable - local vulnerability
SIEM Query:
Not applicable for typical SIEM deployment on mobile devices