Recently it has become clear to me that, although the terms Denial of Service (DoS), Distributed Denial of Service (DDoS) and Brute-Force are used by many, people don't really understand them. This has caused confusion and problems on more than one project, so I thought I would write my thoughts on their similarities, differences and protection mechanisms. A Denial of Service is anything that happens (usually on purpose, but not necessarily) that takes a service off line or makes it unavailable to legitimate users. This could range from a hacker exploiting a vulnerability and taking the service off line, to someone digging up a cable in the road. However, a Denial of Service could also be triggered by legitimate use of a service without any 'vulnerabilities'. Consider a service that performs operations on large sets of data that take a few seconds to complete. If I put in multiple requests for this service then I could tie it up and make it unresponsive for several minute...

I was asked to comment yesterday on the story that emerged about the Google mail accounts that were compromised over the last few days, so I thought I'd put some of my answers down here. First off, Google wasn't compromised ; a set of phishing emails were sent out and a fake Gmail login set up to harvest login details. These were used to set up forwarding rules to copy mail to another account. Unfortunately, although a large number of people are aware of phishing and are (to a certain extent) vigilant, it only takes one person within the organisation to fall for the attack to compromise security. The scammers are becoming better at targeting people and making the initial phishing contact more believable to some people. Phishing is not just about email, although that is the most common avenue for the initial contact. Social media is also commonly used and we have seen the use of SEO to force phishing sites to the top of search engine rankings as well. User education is the o...

I have been talking to a company that provides telephone exchanges and services to companies this week on behalf of a client and it has highlighted a worrying backdoor. It turns out that many of these companies have a way to remotely connect to their exchange for support purposes - they can remotely control, configure and troubleshoot your system to get you back up and running. Exchanges often have additional modems in them to allow for remote connections. This is all very well and good from a managed service point of view, but what about the rest of your network? Can this be exploited to gain entry to your network? Quite possibly in some cases - it certainly needs to be included in your security audit and perimeter testing. Talking about a specific company now, they supply the software to monitor and bill phone calls through the exchange. They remotely install, monitor and manage this software. How do they do that? Well, it turns out that they install LogMeIn on your machine. Now t...

It is quite common in Information Systems to use pseudo code to describe a process. I have often thought that the same principle can be applied to the process of hacking an organisation, which may help people understand the process and how to protect themselves. Below is my proposal for this pseduo-code for the hacking process. This is very much a work in progress. I would welcome feedback on it and I will update it as suggestions are made or as I feel it needs revising. organisation = proposed target organisation. footprint (value, effort, risk) profit = value - (effort * risk) if profit > 0 then   organisation. enumerate ()    select attack_type      case DoS        engage_botnet (myBotnet)       myBotnet. launchDDoS (organisation)      case Access       organisation. gainAccess (myAccount)     ...

While I was answering emails and writing another blog post, I was reminded that lots of people ask me about the seriousness of the threat of attack as they are sceptical. So, I decided to turn on additional logging on my router to view all incoming traffic to see what it is blocking silently. I can tell you that in 2 hours on my home connection here I have had 22 different IP addresses making 47 different attempts to connect to me. One tried to launch a Denial-of-Service (DoS) attack on my web server three times (unsuccessfully), and another attached to my web server to view the options available and didn't bother retrieving any pages - this is a classic sign of footprinting before an attack. The first was host 123-204-6-150.dynamic.seed.net.tw and the second was host164-120-static.29-87-b.business.telecomitalia.it. What were the other 20 connection attempts? Well I don't actually have anything else open on my network, but by logging all connection attempts I can view what pe...