CVE-2026-20407

9.3 CRITICAL

📋 TL;DR

This CVE describes a privilege escalation vulnerability in MediaTek wlan STA drivers where missing bounds checks allow local attackers to gain elevated privileges. Attackers need user execution privileges but no user interaction, affecting devices with vulnerable MediaTek wireless chipsets. The vulnerability enables complete system compromise on affected hardware.

💻 Affected Systems

Products:
  • MediaTek wlan STA drivers
Versions: Specific versions not detailed in CVE; check MediaTek advisory for affected driver versions
Operating Systems: Android, Linux-based systems using MediaTek wireless chipsets
Default Config Vulnerable: ⚠️ Yes
Notes: Affects devices with MediaTek wireless hardware; exact device models not specified in CVE description

⚠️ Risk & Real-World Impact

🔴

Worst Case

Complete system takeover with kernel-level privileges, allowing installation of persistent malware, data theft, and disabling of security controls.

🟠

Likely Case

Local privilege escalation from standard user to root/admin, enabling lateral movement, credential harvesting, and persistence establishment.

🟢

If Mitigated

Limited impact if proper privilege separation exists and vulnerable drivers are isolated from critical systems.

🌐 Internet-Facing: LOW (requires local access, not directly exploitable over network)
🏢 Internal Only: HIGH (local attackers or malware with user privileges can exploit)

🎯 Exploit Status

Public PoC: ✅ No
Weaponized: UNKNOWN
Unauthenticated Exploit: ✅ No
Complexity: MEDIUM

Requires local access and user execution privileges; no public exploit details available

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: Patch ID: WCNCR00464377

Vendor Advisory: https://corp.mediatek.com/product-security-bulletin/February-2026

Restart Required: Yes

Instructions:

1. Check MediaTek advisory for affected driver versions. 2. Apply patch WCNCR00464377. 3. Update device firmware through OEM channels. 4. Reboot device after patching.

🔧 Temporary Workarounds

Restrict driver module loading

linux

Prevent loading of vulnerable wlan STA driver module

echo 'blacklist mt_wlan_sta' >> /etc/modprobe.d/blacklist.conf
rmmod mt_wlan_sta

Disable vulnerable wireless interface

linux

Turn off affected wireless hardware

ip link set wlan0 down
rfkill block wifi

🧯 If You Can't Patch

  • Implement strict privilege separation and least privilege principles
  • Monitor for suspicious privilege escalation attempts and driver loading events

🔍 How to Verify

Check if Vulnerable:

Check driver version: lsmod | grep mt_wlan_sta and compare with MediaTek advisory

Check Version:

modinfo mt_wlan_sta | grep version

Verify Fix Applied:

Verify patch applied: check driver version and ensure WCNCR00464377 patch is listed in system updates

📡 Detection & Monitoring

Log Indicators:

  • Unexpected driver module loads
  • Privilege escalation attempts
  • Kernel memory access violations

Network Indicators:

  • None (local exploit only)

SIEM Query:

EventID=4688 AND ProcessName LIKE '%mt_wlan%' OR EventID=4104 AND ScriptBlockText LIKE '%mt_wlan%'

📊 Metadata

CVE ID: CVE-2026-20407
CVSS v3 Score: 9.3 (CRITICAL)
CVSS Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
CWE: CWE-787
Published: February 2, 2026
Last Updated: February 4, 2026

🤖 AI-assisted analysis, reviewed for accuracy

🔗 References

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