CVE-2023-21101
📋 TL;DR
This CVE describes a use-after-free vulnerability in Android's Widevine DRM plugin caused by a race condition. It allows local privilege escalation without requiring user interaction or additional execution privileges. Affected systems include Android devices with specific SoC implementations.
💻 Affected Systems
- Android devices with Widevine DRM support
📦 What is this software?
Android by Google
⚠️ Risk & Real-World Impact
Worst Case
An attacker gains root privileges on the device, enabling complete system compromise, data theft, and persistent backdoor installation.
Likely Case
Local privilege escalation allowing an attacker to execute code with elevated permissions, potentially accessing sensitive data or installing malicious apps.
If Mitigated
With proper patching and security controls, the vulnerability is eliminated, preventing any privilege escalation attempts.
🎯 Exploit Status
Exploitation requires local access and involves race condition timing, making it moderately complex but feasible for skilled attackers.
🛠️ 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. Apply the June 2023 Android security patch from the device manufacturer. 2. Ensure the patch level is 2023-06-05 or later. 3. Reboot the device after installation.
🔧 Temporary Workarounds
Disable Widevine DRM (not recommended)
androidDisabling the Widevine DRM component may prevent exploitation but will break DRM-protected content playback.
🧯 If You Can't Patch
- Restrict physical access to devices and implement strong device management policies.
- Monitor for unusual privilege escalation attempts using security monitoring tools.
🔍 How to Verify
Check if Vulnerable:
Check Android security patch level in Settings > About phone > Android version. If patch level is before 2023-06-05, the device is likely vulnerable.Check Version:
adb shell getprop ro.build.version.security_patchVerify Fix Applied:
Verify the security patch level is 2023-06-05 or later in device settings.📡 Detection & Monitoring
Log Indicators:
- Unusual process privilege escalation, abnormal Widevine DRM component activity
Network Indicators:
- None - this is a local vulnerability
SIEM Query:
Search for privilege escalation events or abnormal process behavior on Android devices.