CVE-2023-20971
📋 TL;DR
This Android vulnerability allows local attackers to obtain dangerous permissions without user consent due to a logic error in the permission removal code. It enables local privilege escalation without requiring additional execution privileges or user interaction. All Android devices running vulnerable versions are affected.
💻 Affected Systems
- Android OS
📦 What is this software?
Android by Google
⚠️ Risk & Real-World Impact
Worst Case
An attacker with physical or remote access could gain full system privileges, access sensitive data, install malware, or compromise device integrity.
Likely Case
Malicious apps could escalate privileges to access protected resources like contacts, location, camera, or storage without user consent.
If Mitigated
With proper app sandboxing and security updates, impact is limited to specific vulnerable versions only.
🎯 Exploit Status
Requires local access and ability to execute code, but no user interaction needed. Exploit would need to bypass app sandboxing first.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Android Security Bulletin August 2024 and earlier patches (June 2023 for Pixel)
Vendor Advisory: https://source.android.com/security/bulletin/2024-08-01
Restart Required: Yes
Instructions:
1. Check for Android system updates in Settings > System > System update. 2. Install latest security patch. 3. Reboot device. 4. For enterprise: push updates via MDM/EMM solutions.
🔧 Temporary Workarounds
Restrict app installations
androidOnly install apps from trusted sources like Google Play Store and disable unknown sources installation.
adb shell settings put secure install_non_market_apps 0
Review app permissions
androidRegularly audit and revoke unnecessary permissions from installed applications.
🧯 If You Can't Patch
- Isolate vulnerable devices from sensitive networks and data
- Implement application allowlisting to prevent unauthorized app execution
🔍 How to Verify
Check if Vulnerable:
Check Android build number in Settings > About phone > Build number. Compare against patched versions in security bulletins.Check Version:
adb shell getprop ro.build.version.security_patchVerify Fix Applied:
Verify security patch level is August 2024 or later in Settings > About phone > Android version > Security update.📡 Detection & Monitoring
Log Indicators:
- Unexpected permission grants in logcat
- PermissionManagerService anomalies
- Apps requesting dangerous permissions without user prompts
Network Indicators:
- Unusual network activity from apps with escalated privileges
SIEM Query:
source="android_logs" AND ("Permission granted" OR "removePermission") AND NOT "user_consent"