CVE-2023-21144
📋 TL;DR
This vulnerability in Android's notification system allows remote attackers to cause temporary denial of service by sending specially crafted notifications that trigger long-running operations. It affects Android 11, 12, 12L, and 13 devices, 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
Device becomes temporarily unresponsive or crashes, disrupting all user activities and potentially requiring a reboot.
Likely Case
Notification system becomes unresponsive, causing missed alerts and degraded user experience until the process terminates.
If Mitigated
Minimal impact if patched; otherwise, temporary service disruption limited to notification functionality.
🎯 Exploit Status
Exploitation is straightforward via remote notification delivery, but no public proof-of-concept has been documented.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Android Security Bulletin June 2023 patches
Vendor Advisory: https://source.android.com/security/bulletin/2023-06-01
Restart Required: Yes
Instructions:
1. Check for system updates in device settings. 2. Install the June 2023 Android security update. 3. Reboot the device after installation.
🔧 Temporary Workarounds
Disable notifications from untrusted sources
androidPrevent exploitation by restricting notification permissions for unknown or suspicious apps.
Navigate to Settings > Apps & notifications > Notifications > App notifications, then disable for risky apps.
🧯 If You Can't Patch
- Monitor and block malicious notification sources at network level using firewalls or security gateways.
- Use mobile device management (MDM) solutions to restrict app installations and notification permissions.
🔍 How to Verify
Check if Vulnerable:
Check Android version in Settings > About phone > Android version; if it's 11, 12, 12L, or 13 without June 2023 patches, it's vulnerable.Check Version:
adb shell getprop ro.build.version.releaseVerify Fix Applied:
Verify the Android security patch level is dated June 2023 or later in Settings > About phone > Android security patch level.📡 Detection & Monitoring
Log Indicators:
- Logcat entries showing ANR (Application Not Responding) or crashes in NotificationContentInflater.java.
Network Indicators:
- Unusual notification traffic from external sources to Android devices.
SIEM Query:
Example: 'source="android_logs" AND ("ANR" OR "NotificationContentInflater")'