In my department, we block about 92% of our total email (around 2.5 billion per day) at the network edge without accepting the message. When we do that, we don't see any traffic from that IP anymore and don't keep stats on it due to the overwhelming volume of mail. However, we do keep stats on mail that we block with our content filter. I decided to go and calculate how much spam we receive from each country by mapping the source IP back to its source country... more
There have been a number of attacks on the root name servers over the years, and much written on the topic. (A few references are here, here and here.) Even if you don't know exactly what these servers do, you can't help but figure they're important when the US government says it is prepared to launch a military counterattack in response to cyber-attacks on them. more
OK, you know things are getting bad when Ameritrade leaks its customer information yet again, and I don't even bother to report it because it's not news anymore. Well, recent updates to the story have prompted me to correct that omission. Yes, it happened again. Roughly a month ago, correspondents began to receive pump-n-dump spam to tagged email addresses which they had given only to Ameritrade... This now marks the third major confirmed leak of customer information from Ameritrade. In addition, the Inquirer reported the loss of 200,000 Ameritrade client files in February 2005. One correspondent informs me that this has happened to him on four or five previous occasions. more
I've written recently about a general purpose method called DNS Response Policy Zones (DNS RPZ) for publishing and consuming DNS reputation data to enable a market between security companies who can do the research necessary to find out where the Internet's bad stuff is and network operators who don't want their users to be victims of that bad stuff... During an extensive walking tour of the US Capitol last week to discuss a technical whitepaper with members of both parties and both houses of the legislature, I was asked several times why the DNS RPZ technology would not work for implementing something like PROTECT-IP. more
Distributed Denial-of-Service (DDoS) attacks will become larger in scale, harder to mitigate and more frequent, says Deloitte in its annual Global Predictions report. more
I keep hearing stories of people using "foldering" for covert communications. Foldering is the process of composing a message for another party, but instead of sending it as an email, you leave it in the Drafts folder. The other party then logs in to the same email account and reads the message; they can then reply via the same technique. Foldering has been used for a long time, most famously by then-CIA director David Petraeus and his biographer/lover Paula Broadwell. Why is foldering used? more
Here we are, all the way up to Myth #4! That makes this the 4th installment of our 10 part series on the top IPv6 Security Myths. This myth is one of my favorite myths to bust when speaking with folks around the world. The reason for that is how many otherwise well-informed and highly experienced engineers, and others, hold this myth as truth. It's understandable, really. more
We're back again with part 3 in this 10 part series that seeks to bust 10 of the most common IPv6 security myths. Today's myth is a doozy. This is the only myth on our list that I have seen folks raise their voices over. For whatever reason, Network Address Translation (NAT) seems to be a polarizing force in the networking world. It also plays a role in differentiating IPv4 from IPv6. more
Today we continue with part 2 of the 10 part series on IPv6 Security Myths by debunking one of the myths I overhear people propagating out loud far too much: That you don't need to worry about security because IPv6 has it built into the protocol. In this post, we'll explore several of the reasons that this is in fact a myth and look at some harsh realities surrounding IPv6 security. more
A report recently released by McAfee Advanced Threat Research (ATR) revealed a fileless attack targeting organizations involved with the Pyeongchang Olympics. more
In my last blog post I shared some of the general security challenges that come with the Internet of Things (IoT). In this post, I will focus on one particular security risk: distributed denial of service (DDoS) attacks. Even before the age of IoT, DDoS attacks have been turning multitudes of computers into botnets, attacking a single target and causing denial of services for the target's users. By "multitudes" we can be talking about thousands or even millions of victim devices. Now add IoT into the equation... more
I had quite an interesting experience recently. I was hired by a company to perform a vulnerability assessment and penetration test on their network. During the initial meeting, one of the key technical staff presented me with a challenge; He handed over the NTLM hash of the domain Administrator account and challenged me to decipher it. He explained that the complexity and length of the password would prevent me from deciphering it during the time allotted for the project. He was actually quite confident in my impending failure... more
Now that IPv6 is being actively deployed around the world, security is more and more a growing concern. Unfortunately, there are still a large number of myths that plague the IPv6 security world. These are things that people state as fact but simply aren't true. While traveling the world, talking to the people who've already deployed IPv6, I've identified what I believe are the ten most common IPv6 security myths. more
Due to increased legislative interest in this topic, CENTR says there is a pressing need for comprehensive educational material on the technical capabilities of the DNS, ccTLDs and their role in the internet ecosystem. more
While typosquatting is not a new phenomenon, recent research highlights that it is being used to collect sensitive corporate information from employees and lure consumers to interact with dubious websites. ... Security consultancy Godai Group recently uncovered the use of a specific type of typosquat - a "doppelganger domain" - to collect sensitive enterprise information via email-based attacks. more