CVE-2023-35670
📋 TL;DR
This vulnerability allows local attackers to write files to other apps' private directories on Android devices through a path traversal flaw in MediaProvider's FileUtils.java. It enables local privilege escalation without requiring user interaction or additional permissions. All Android devices running vulnerable versions are affected.
💻 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
Complete device compromise where an attacker gains full system access, can read/modify any app's private data, install persistent malware, or disable security controls.
Likely Case
Data theft from other applications, injection of malicious content into trusted apps, or privilege escalation to perform unauthorized actions.
If Mitigated
Limited impact with proper app sandboxing and SELinux policies preventing full system compromise, though data leakage between apps may still occur.
🎯 Exploit Status
Exploitation requires local access to device but no user interaction. Path traversal vulnerability is straightforward to exploit once identified.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: September 2023 Android Security Bulletin or later
Vendor Advisory: https://source.android.com/security/bulletin/2023-09-01
Restart Required: Yes
Instructions:
1. Apply September 2023 Android Security Patch
2. Update device through Settings > System > System Update
3. Reboot device after update completes
🔧 Temporary Workarounds
Disable unnecessary apps
androidReduce attack surface by disabling unused applications that could be targeted
Restrict app installations
androidOnly allow app installations from trusted sources like Google Play Store
🧯 If You Can't Patch
- Implement strict app isolation policies and monitor for unusual file access patterns
- Use mobile device management (MDM) solutions to restrict app permissions and monitor for suspicious behavior
🔍 How to Verify
Check if Vulnerable:
Check Android security patch level in Settings > About Phone > Android Version. If before September 2023, device is vulnerable.Check Version:
adb shell getprop ro.build.version.security_patchVerify Fix Applied:
Verify security patch level shows 'September 5, 2023' or later in Settings > About Phone > Android Version.📡 Detection & Monitoring
Log Indicators:
- Unusual file write operations to other apps' private directories in system logs
- MediaProvider process accessing unexpected file paths
Network Indicators:
- Not applicable - local vulnerability only
SIEM Query:
Not applicable for typical Android deployments🔗 References
- https://android.googlesource.com/platform/packages/providers/MediaProvider/+/db3c69afcb0a45c8aa2f333fcde36217889899fe
- https://source.android.com/security/bulletin/2023-09-01
- https://android.googlesource.com/platform/packages/providers/MediaProvider/+/db3c69afcb0a45c8aa2f333fcde36217889899fe
- https://source.android.com/security/bulletin/2023-09-01
