CVE-2023-20956
📋 TL;DR
This CVE describes an out-of-bounds write vulnerability in Android's C2SurfaceSyncObj.cpp import function due to missing bounds checks. It could allow local information disclosure but requires system execution privileges to exploit. Affected users include those running Android 12, 12L, or 13 without the March 2023 security patches.
💻 Affected Systems
- Android
📦 What is this software?
Android by Google
Android by Google
Android by Google
⚠️ Risk & Real-World Impact
Worst Case
An attacker with system privileges could write arbitrary data to adjacent memory, potentially leading to information disclosure, privilege escalation, or system instability.
Likely Case
Local information disclosure where an attacker with system privileges could read sensitive data from adjacent memory regions.
If Mitigated
No impact if proper privilege separation is enforced and attackers cannot obtain system execution privileges.
🎯 Exploit Status
Exploitation requires system execution privileges and knowledge of memory layout. No user interaction needed once privileges are obtained.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: March 2023 Android Security Bulletin
Vendor Advisory: https://source.android.com/security/bulletin/2023-03-01
Restart Required: Yes
Instructions:
1. Check for available system updates in Settings > System > System update. 2. Install the March 2023 Android security update. 3. Reboot the device after installation completes.
🔧 Temporary Workarounds
Restrict system privileges
androidLimit applications and users with system execution privileges to reduce attack surface.
🧯 If You Can't Patch
- Implement strict application sandboxing to prevent privilege escalation to system level
- Monitor for unusual system privilege usage and memory access patterns
🔍 How to Verify
Check if Vulnerable:
Check Android version in Settings > About phone > Android version. If running Android 12, 12L, or 13 without March 2023 security patch, device is vulnerable.Check Version:
adb shell getprop ro.build.version.security_patchVerify Fix Applied:
Verify Android security patch level in Settings > About phone > Android security update. Should show 'March 5, 2023' or later.📡 Detection & Monitoring
Log Indicators:
- Unusual memory access patterns in system logs
- Processes attempting to access C2SurfaceSyncObj.cpp with system privileges
Network Indicators:
- No network indicators - this is a local vulnerability
SIEM Query:
No specific SIEM query as this is a local memory corruption vulnerability