CVE-2026-20410
📋 TL;DR
This CVE describes an out-of-bounds write vulnerability in imgsys (likely MediaTek image processing subsystem) that allows local privilege escalation. Attackers with initial System privilege access can exploit this to gain higher privileges without user interaction. This affects devices using vulnerable MediaTek chipsets.
💻 Affected Systems
- MediaTek chipsets with imgsys subsystem
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise allowing attackers to execute arbitrary code with kernel privileges, potentially taking full control of the device.
Likely Case
Local privilege escalation from System to kernel-level access, enabling persistence, data theft, and further system manipulation.
If Mitigated
Limited impact if proper privilege separation and kernel hardening are implemented, though still a serious local vulnerability.
🎯 Exploit Status
Exploitation requires existing System privilege but no user interaction; missing bounds check suggests straightforward exploitation once initial access is obtained.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patch ID: ALPS10362552
Vendor Advisory: https://corp.mediatek.com/product-security-bulletin/February-2026
Restart Required: Yes
Instructions:
1. Check MediaTek security bulletin for affected chipset models. 2. Obtain firmware update from device manufacturer. 3. Apply patch ALPS10362552. 4. Reboot device to load patched kernel/driver.
🔧 Temporary Workarounds
Restrict System privilege access
linuxLimit which processes/users can obtain System privilege to reduce attack surface
Review and tighten SELinux/AppArmor policies
Audit processes running with System privilege
🧯 If You Can't Patch
- Implement strict kernel hardening (KASLR, stack protection, etc.) to make exploitation more difficult
- Monitor for unusual privilege escalation attempts and System privilege abuse
🔍 How to Verify
Check if Vulnerable:
Check kernel/driver version against MediaTek's affected chipset list; examine if imgsys driver is present and unpatchedCheck Version:
Check kernel version: uname -r; Check MediaTek driver versions in /sys/class/ or dmesg outputVerify Fix Applied:
Verify patch ALPS10362552 is applied in kernel/driver version; check that bounds checking is implemented in imgsys code📡 Detection & Monitoring
Log Indicators:
- Kernel panic or oops messages related to imgsys
- Unexpected privilege escalation from System to kernel context
- Memory corruption warnings in kernel logs
Network Indicators:
- Not applicable - local exploitation only
SIEM Query:
Search for: 'imgsys' AND ('panic' OR 'oops' OR 'segfault') in kernel logs OR privilege escalation from uid=1000 to uid=0