Beware of port scanning
When your computer connects to the Internet, it exposes communication ports for legitimate applications to use. But hackers can also sneak onto your computer through these open ports if they are not properly shielded.
When hackers search for exploitable computers over the Internet, they launch special “sniffer” utilities that probe arbitrary IP addresses for the presence of vulnerabilities. These automated tools test Internet users’ computers for broadcasting ports – ports that are ready to accept connections from the Internet or a LAN.
These ports, sometimes called “server” ports because they are “serving themselves up” to hackers, may be being kept open by a vulnerable application (for example, an old game that hasn’t been updated or flawed Instant Messaging software that accepts file transfers). If this is the case, hackers can exploit them to establish an underground connection channel and run malicious command-and-control software on your machine.
The solution to these threats is:
- timely installation of updates for your installed programs and Windows components;
- a reliable firewall that prevents port scanning and limits port exposure to local access only;
- the use of legitimate software that you both need and trust.
Posted in Security Tip of the Week
April 15th, 2008 at 3:54 am
It is so frightning that these days even when we know we have kept everything up to date, a new threat might get through. We’ve received letters from time to time warning of a new virus that will wipe everything, verified by Microsoft and Norton (for example) Pass it on… I don’t pass it on I think this is a circular letter that will create a denial of service as I notice happens every time one of these gets out and everyone is sending on to everyone. Yet one day such a warning could be valid. But I think that such a virus will have already got us before it can be identified to warn about!
Erc
April 15th, 2008 at 8:20 pm
Hi. I remember years ago, a virus circulating was called “little Red Riding Hood and the Big Bad Wolf.” I recall that I sent the warning email to friends/family and co-workers.. Well needless to say….months later a distant cousin received the forewarned malicious email labeled as per my warning email content…she had not paid my warning attention and as a result required her entire computer rebuilt!!! It is always difficult to decipher between what is a real threat and those that are perceived or just for someone else’s fun and games. I do believe that all we can do is exercise with caution, take all the steps that we can in order to protect ourselves, and then hope for the best.
April 16th, 2008 at 7:32 pm
Outpost rocks, port scans blocked several times. Once was a chat session with a HP printer tech to fix my printer and he scanned my port to see if I was still on chat with him. After the block he asked if I was still there. He thought that we got disconnected
April 20th, 2008 at 11:39 am
Outpost is a good firewall,Online Armour probably even better.If you use firewalls of this caliber,coupled with a good updated antivirus,you are safe.But its probably just as important to make sure your whole computer is patched up all over.If there are holes,they will be used.
May 24th, 2008 at 1:28 pm
FTP in passive mode transmitting each block through another port: your solution getting around this problem ? With one provider, I had to switch to active mode, but it’s not the recommended solution, therefore the question. Does it not look rather like port scanning ?