CVE-2018-9447
📋 TL;DR
This vulnerability allows local attackers to crash emergency callback mode on Android devices due to a missing null check in the EmergencyCallbackModeExitDialog component. It affects Android devices running vulnerable versions, requiring no user interaction or special privileges for exploitation.
💻 Affected Systems
- Android
📦 What is this software?
Android by Google
Android by Google
Android by Google
Android by Google
⚠️ Risk & Real-World Impact
Worst Case
Emergency callback mode becomes unavailable, potentially preventing emergency calls in critical situations where this mode is active.
Likely Case
Temporary denial of service affecting emergency callback functionality until device restart or mode reset.
If Mitigated
No impact if patched or if emergency callback mode is not actively used.
🎯 Exploit Status
Exploitation requires local access but no authentication or user interaction. The vulnerability is in a system component accessible to local apps.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Android Security Patch Level 2018-08-01 or later
Vendor Advisory: https://source.android.com/security/bulletin/pixel/2018-08-01
Restart Required: Yes
Instructions:
1. Check for system updates in Settings > System > Advanced > System update. 2. Install the August 2018 Android security patch. 3. Reboot device after installation.
🔧 Temporary Workarounds
Disable emergency callback mode if not needed
androidEmergency callback mode is a specialized feature; disabling it if not required eliminates the attack surface.
🧯 If You Can't Patch
- Restrict installation of untrusted applications to reduce local attack vectors.
- Monitor for abnormal crashes in telephony/emergency services components.
🔍 How to Verify
Check if Vulnerable:
Check Android version and security patch level in Settings > About phone > Android version. If security patch level is before 2018-08-01 and Android version is 8.0 or 8.1, device is vulnerable.Check Version:
adb shell getprop ro.build.version.security_patchVerify Fix Applied:
Confirm security patch level is 2018-08-01 or later in Settings > About phone > Android version.📡 Detection & Monitoring
Log Indicators:
- Unexpected crashes or null pointer exceptions in EmergencyCallbackModeExitDialog or telephony service logs
SIEM Query:
Search for error logs containing 'EmergencyCallbackModeExitDialog' or 'NullPointerException' in telephony-related processes.