|Port Listener 1.0|
|Created by Willems Davy|
What is it ?:
Port listener is a simple program that runs in the system tray, when activated, it opens a port that u specified for monotering, so u can check if a certain user connect's to that port. The program will make a sound (if u specified one) when a user connects, it will also give the user's ip host etc and will keep a log of all connects. The program also keeps sending a text wich u specified to the user until he disconects from that port so he knows he has been catched.
What is it good for ?:
Well the program is created to catch those guys, that do portscans on your system for a specific port for instance the trojan (a trojan is a kind of virus that lets user control your pc remotly) sub7 wich mostly runs at port 27374, so u let the program monitor on that port. Then when someone is doing portscans to see if u are infected by sub7 u will be alarmed of this and the user keeps getting the text u specified in his portscanner (like 7th sphere) until he closes or reset the portscanner. So the person who did the portscan will know he is caught (that's what i like frigthen them a bit :)). U can then check the log for the persons ip and host and with this information u can find out what provider there using and find their providers web site to sent them an email informing them of the person that does these portscans (give an extract of the log with the date and time ) and they will make sure the person will be notified of these 'illegal' (in some countries portscanning is legal) actions.
That's for portscans if the port is known, other persons seem to do a full port scan on your system starting from port 1 and going up to see wich one is open, if you want to catch those ones, i suggest putting the port to monitor on a low (unused) number like 5 or something, so they won't get far and will imediatly know they are cought.
What Does port in use mean ?:
Well it means what it says, that the port is used by another program, for instance if u set the port to monitor on 21 and you are running an ftp client , u will get such an error.
What about port 139 ?:
For some reason (can't find out why) this port is being monitored but whenever someone connects to this port, no text is being send to him, however u will be notified of the connect from that person (it's also logged).
which port should i monitor ?:
well the most common one scanned for in this time is the default sub7 port 27374 i had most connects from users on that port then there are other trojans (don't know all of them nor all the ports) like Netbus wich mostly runs at port 12345 there some other trojan BO but i don't know at what port it runs. and if you wan't to catch users that do full port scans on your system to find open ports , set it to a low numbered port.
What about Red and yellow Lightening icon in systemtray ?:
The program runs from the systemtray so it has an icon there, the icon is normally a YELLOW lightening, when it's activated and monitoring a port, The icon is a DISBALED YELLOW lightening when it isn't monitoring a port so when program isn't activated, The icon is a RED lightining when someone connected / had connected , it keeps red until you double click (left mousebutton) the tray icon or chose one of the three settings, misc log or settings then the icon will be come a YELLOW lightening again.