CVE-2020-26652
📋 TL;DR
This vulnerability in the rtl8812au Wi-Fi driver allows attackers to cause a denial of service by exploiting a flaw in the nl80211_send_chandef function. Systems using this driver for wireless network interfaces are affected. The vulnerability can crash the kernel or cause system instability.
💻 Affected Systems
- rtl8812au driver
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Kernel panic leading to complete system crash and requiring physical reboot, potentially causing data loss or service disruption.
Likely Case
Wireless interface crash requiring driver reload or system restart, disrupting network connectivity temporarily.
If Mitigated
Minimal impact if systems are patched or workarounds applied; isolated to wireless functionality only.
🎯 Exploit Status
Exploitation requires sending crafted nl80211 messages to the wireless interface. No public exploit code has been confirmed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Fixed in later versions of rtl8812au driver
Vendor Advisory: https://github.com/aircrack-ng/rtl8812au/issues/730
Restart Required: Yes
Instructions:
1. Update rtl8812au driver to latest version from official repository. 2. Rebuild and reinstall driver. 3. Reboot system to load new driver.
🔧 Temporary Workarounds
Disable vulnerable driver
linuxTemporarily disable the rtl8812au driver to prevent exploitation
sudo modprobe -r 8812au
echo 'blacklist 8812au' | sudo tee /etc/modprobe.d/blacklist-8812au.conf
Restrict wireless interface access
linuxLimit network access to wireless interfaces using firewall rules
sudo iptables -A INPUT -i wlan0 -j DROP
sudo iptables -A OUTPUT -o wlan0 -j DROP
🧯 If You Can't Patch
- Disable wireless functionality and use wired connections only
- Implement strict network segmentation to isolate wireless networks
🔍 How to Verify
Check if Vulnerable:
Check driver version: lsmod | grep 8812au and verify if version is v5.6.4.2 or earlierCheck Version:
modinfo 8812au | grep versionVerify Fix Applied:
Verify updated driver version and ensure system remains stable during wireless operations📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages in /var/log/kern.log
- Driver crash messages
- Wireless interface disconnection events
Network Indicators:
- Unusual nl80211 protocol traffic to wireless interfaces
- Sudden wireless connectivity loss
SIEM Query:
source="kern.log" AND "panic" OR "8812au" OR "wireless driver crash"