CVE-2025-20713
📋 TL;DR
This CVE describes an out-of-bounds write vulnerability in MediaTek's wlan AP driver due to incorrect bounds checking. It allows local privilege escalation from System to kernel-level access without user interaction. Affects devices using MediaTek Wi-Fi chipsets with vulnerable driver versions.
💻 Affected Systems
- MediaTek Wi-Fi chipsets with wlan AP driver
📦 What is this software?
Openwrt by Openwrt
Openwrt by Openwrt
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with kernel-level code execution, enabling persistent backdoors, data theft, and device bricking.
Likely Case
Local privilege escalation allowing attackers to bypass security controls, install malware, and access sensitive system resources.
If Mitigated
Limited impact if proper kernel hardening, SELinux/apparmor, and driver signing are enforced.
🎯 Exploit Status
Exploitation requires existing System privilege; driver-level vulnerabilities often attract sophisticated attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: WCNCR00432661
Vendor Advisory: https://corp.mediatek.com/product-security-bulletin/October-2025
Restart Required: Yes
Instructions:
1. Check device manufacturer for firmware updates. 2. Apply MediaTek patch WCNCR00432661. 3. Reboot device. 4. Verify driver version.
🔧 Temporary Workarounds
Disable vulnerable driver module
linuxTemporarily disable the wlan AP driver if not essential
modprobe -r mtk_wlan_ap_driver
🧯 If You Can't Patch
- Implement strict SELinux/apparmor policies to limit driver capabilities
- Monitor for unusual privilege escalation attempts and driver module loading
🔍 How to Verify
Check if Vulnerable:
Check driver version: lsmod | grep mtk_wlan_ap and compare with patched versionCheck Version:
modinfo mtk_wlan_ap_driver | grep versionVerify Fix Applied:
Verify patch WCNCR00432661 is applied in system logs or driver version📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs
- Driver crash reports
- Unexpected privilege escalation in audit logs
Network Indicators:
- Unusual driver module loading patterns
SIEM Query:
source="kernel" AND "mtk_wlan_ap" AND ("panic" OR "oops")