Realtek RTL8811AU Monitor mode issues on Kernel 5.4
Hi, i have been having an issue since the recent upgrade to Kali 2020.1 and the new kernel 5.4. I have spent a few days trawling both this forum and the wider web for answers or resolution but have not come up with anything concrete.
I am using the Realtek AWUS036ACS wireless adapter with the RTL8811AU chipset, which worked perfectly on the previous 4.19 kernel.
However since the upgrade to 5.4, i have had issues with the monitor mode. The device itself is recognized when plugged in and i can use this to connect to wifi with no issues. However when putting this into monitor mode (using either airmon-ng or iwconfig) this shows as monitor mode, but will crash/error when attempting to use (such as wifite or airgeddon).
Example below is using airmon-ng to enter monitor mode, confirmed by iwconfig, and then wifite throwing an error about no monitor mode. The same is shown when using iwconfig to put the device into monitor mode:
Code:
user@kali:~$ sudo airmon-ng check kill
user@kali:~$ sudo airmon-ng start wlan1
PHY Interface Driver Chipset
phy0 wlan0 iwlwifi Intel Corporation Wireless 7260 (rev bb)
phy3 wlan1 88XXau Realtek Semiconductor Corp.
(monitor mode enabled)
user@kali:~$ sudo iwconfig
eth0 no wireless extensions.
wlan1 IEEE 802.11b ESSID:"" Nickname:"<WIFI@REALTEK>"
Mode:Monitor Frequency:2.457 GHz Access Point: Not-Associated
Sensitivity:0/0
Retry:off RTS thr:off Fragment thr:off
Encryption key:off
Power Management:off
Link Quality=0/100 Signal level=-100 dBm Noise level=0 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0
lo no wireless extensions.
wlan0 IEEE 802.11 ESSID:off/any
Mode:Managed Access Point: Not-Associated Tx-Power=22 dBm
Retry short limit:7 RTS thr:off Fragment thr:off
Encryption key:off
Power Management:on
user@kali:~$ sudo wifite --kill
. .
. ? . . ? `. wifite2 2.5.0
: : : (?) : : : an automated wireless auditor forked from @derv82
`. ? ` /?\ ? . https://github.com/kimocoder/wifite2
` /???\
[+] option: kill conflicting processes enabled
Interface PHY Driver Chipset
-----------------------------------------------------------------------
1. wlan0 phy0 iwlwifi Intel Corporation Wireless 7260 (rev bb)
2. wlan1 phy3 88XXau Realtek Semiconductor Corp.
[+] Select wireless interface (1-2): 2
[+] enabling monitor mode on wlan1... failed
failed
[!] Error: Cannot find any interfaces in monitor mode
[!] Full stack trace below
[!] Traceback (most recent call last):
[!] File "/usr/lib/python3/dist-packages/wifite/__main__.py", line 98, in entry_point
[!] wifite.start()
[!] File "/usr/lib/python3/dist-packages/wifite/__main__.py", line 51, in start
[!] Configuration.get_monitor_mode_interface()
[!] File "/usr/lib/python3/dist-packages/wifite/config.py", line 152, in get_monitor_mode_interface
[!] cls.interface = Airmon.ask()
[!] File "/usr/lib/python3/dist-packages/wifite/tools/airmon.py", line 332, in ask
[!] iface.interface = Airmon.start(iface)
[!] File "/usr/lib/python3/dist-packages/wifite/tools/airmon.py", line 203, in start
[!] raise Exception('Cannot find any interfaces in monitor mode')
[!] Exception: Cannot find any interfaces in monitor mode
[!] Exiting
So it would appear that although iwconfig shows this is in monitor mode, it actually is not changing this. I have been able to change my internal PCI wifi to monitor mode and back in the same way which works in wifite (although not very strong).
My initial thought was the drivers, so have removed and reinstalled both the "firmware-realtek" and "realtek-rtl88xxau-dkms" drivers (auto installed at upgrade), which has had no effect. I have also searched for alternative drivers and installed to see if this has any impact, but again none.
When checking dmesg after the device has been plugged in, no (obvious) errors are shown.
Code:
user@kali:~$ sudo dmesg
[ 7077.001882] usb 1-2.3: new high-speed USB device number 16 using xhci_hcd
[ 7077.026451] usb 1-2.3: New USB device found, idVendor=0bda, idProduct=0811, bcdDevice= 2.00
[ 7077.026467] usb 1-2.3: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 7077.026477] usb 1-2.3: Product: 802.11ac WLAN Adapter
[ 7077.026486] usb 1-2.3: Manufacturer: Realtek
[ 7077.026496] usb 1-2.3: SerialNumber: 00e04c000001
After searching this forum, it appears a lot of others are having issues with WIFI on the new kernel, but mine is specifically monitor mode. My only guess is that this is an issue with the driver, but having been able to use the Wifi i am not sure.
Anyone have any guidance here? My thoughts are to find a driver which works with both the Wifi and monitor mode for this device, or downgrade the kernel to 4.19. Or do i just stick with the current driver&kernel and hope that is something bigger and out of my control that will be fixed down the line?
Thanks
Ovi
