MODEM USERS READ ON

This week, we are continuing with:

 

DoS/DDoS (Denial of Service or Distributed Denial of Service)

This is an act intended to force a computer or computer network to stop functioning on the Internet. Common attacks involved sending a huge amount of traffic in the form of web requests to one or multiple PCs or Servers, this traffic can come from PCs across the Internet being infected with malware. A PC or Server could also be infected with a Trojan which once executed could turn the PC or Server into a Web server. The Attacker could then flood that PC or Server with huge amounts of requests and/or data, too many for the system to handle and taking up huge amounts of bandwidth and/or Hard Disk space, thus causing the system to fall over (stop responding) and becoming unresponsive to Network or Web requests, Websites becoming unavailable, email becoming unavailable, forcing the Router(s) to keep rebooting etc.

As an example of how a huge amount of traffic can bring a service down; in June 2009 when it was announced that Michael Jackson had passed away, the traffic going through Google from users searching for information on him, the Google News service became crippled and went down temporarily displaying an error message for a short amount of time. This was a genuine Load issue, though also in 2009 a huge Denial of Service attack was experienced by Facebook users when an attack was aimed at a Georgian Blogger, thousands of infected systems were without their knowledge sending huge amounts of traffic to the Bloggers page overloading the Facebook servers, this left the service un-usable for around two hours.

Dialler

A Dialler is a program used to connect to the Internet or a computer network (such as a VPN or Virtual Private Network), they connect over an analogue or ISDN telephone line. Diallers are used when an ADSL connection is not available, so the computer’s modem is used to connect to the Internet or Network instead.

Rogue diallers secretly install code on a user’s system causing modems to connect to the Internet via a premium-rate number, whose profits are siphoned off to the scammers. Only computers using a telephone or ISDN line can be affected as ADSL modem/routers cannot be used to dial out.

The age of Dial Up Internet seems such a distant memory, but those still using it are at an extremely high risk of becoming infected and most common infections with Dial Up users are Dialler infections. These will either ask you to press ok to connect to a specific site which could turn out to be a specific type of content, or the user would have no idea that the modem is dialling out until their phone bill comes in.

Dial Up Internet opens up many ports in the computers operating system allowing a flood of inbound connections which if you are not 100% protected, will inevitably lead to your PC becoming so badly infected rendering the PC unusable, and even worse, facing a HUGE phone bill caused by Dialler infections.

If you do still use a Dial Up Connection, either because you live in a rural part of the UK which unfortunately still cannot receive Broadband or Cable, or use Dial Up for when you are out and about and have not looked into 3G USB devices, then here are some ways to protect yourself:

• Make sure you install adequate Anti Virus software, although free Antivirus software can be good, some do not offer real time scanning or regular updates, some do not come with a Firewall. It is worth investing in a good Anti Virus package offering the real time scanning, regular automatic updates and a good Firewall.
• If you use a laptop to connect to the Internet when out and about, invest in a 3G USB dongle, they don’t dial a number to get an internet connection.
• If you must use a modem to dial an Internet connection, make sure you unplug the modem cable when you are not using it, this will stop any diallers making calls when you are not using the modem.
• Make sure you keep your Operating System updated with the latest security patches.

 

DNS (Domain Name Service or Domain Name Server)

A Domain Name Server assists Internet users navigate their way around the internet by translating IP addresses to Domain Names.  Every PC has its own unique IP address which is a string of numbers e.g. 81.0.111.222 could translate to www.exampledomain.com

Dropper

A Dropper is a program which is used to install Malware or a virus on to a PC. The Dropper is designed in such a way that it can be undetected by Anti Virus programs.

The Glossary will continue next week.  In the meantime, should you have any questions, please feel free to contact us!