My "Failed Attempts" log shows strange activities, namely the following:
Authen Failed/Reason Unknown
Username:
?~?~?~?~?~?~?~?~?~?~?~?~?U~-~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?DZd~r~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?
Username:
jjjqjuQuuuj j!j j5jj jeoD1V2gwo)WPV'rA|kEou#
Username:
~?~?~?~?ez1v~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~??~?~?~?~?~??~?~?~?~?~?~?~?~>y^KW>spg~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~ )I4y~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~?~
And on and on and on... This happens several times.
All my successful Authentications from my dial up server come on Nas port numbers such as Async35, Async34, etc...
Successful ACS authentication when I access network devices use Nas Ports 510, 480, 479, etc..
These faile attempts are from Nas Port tty33.
Does it appear someone may be trying a buffer overflow? What is tty33?
Thanks
