Threat Intelligence

Painting Ourselves Into a Corner with Path MTU Discovery

In Tony Li's article on path MTU discovery we see this text: "The next attempt to solve the MTU problem has been Packetization Layer Path MTU Discovery (PLPMTUD). Rather than depending on ICMP messaging, in this approach, the transport layer depends on packet loss to determine that the packet was too big for the network. Heuristics are used to differentiate between MTU problems and congestion. Obviously, this technique is only practical for protocols where the source can determine that there has been packet loss. Unidirectional, unacknowledged transfers, typically using UDP, would not be able to use this mechanism. To date, PLPMTUD hasn't demonstrated a significant improvement in the situation." Tony's article is (as usual) quite readable and useful, but my specific concern here is DNS... more

Anti-Spoofing, BCP 38, and the Tragedy of the Commons

In the seminal 1968 paper "The Tragedy of the Commons" , Garrett Hardin introduced the world to an idea which eventually grew into a household phrase. In this blog article I will explore whether Hardin's tragedy applies to anti-spoofing and Distributed Denial of Service (DDoS) attacks in the Internet, or not... Hardin was a biologist and ecologist by trade, so he explains "The Tragedy of the Commons" using a field, cattle and herdsmen. more

‘First True’ Native IPv6 DDoS Attack Reported

Possibly the first documented native IPv6 DDoS attack reported today suggests a DNS dictionary attack which originated from around 1,900 different native IPv6 hosts, on more than 650 different networks. more

FBI, DHS Release Technical Details on North Korea’s DDoS Botnet Infrastructure

U.S. Department of Homeland Security (DHS) and the FBI today released a technical alert based joint-effort analysis of methods behind North Korea’s cyberattacks. more

Cloud Computing Can Make You More Secure

The number one concern cited for avoiding cloud computing is security. And there is a reason for that. Cloud providers have demonstrated some spectacular failures in the past, including Amazon's near total shutdown of an entire region, Dropbox's authentication snafu, and innumerous cloud providers that go belly-up. However, in the long run, cloud computing is destined to become more secure than in-house IT. I will briefly describe two dynamics in the industry that point in that direction, with substantiating evidence. more

What’s ARC?

DMARC is an anti-phishing technique that AOL and Yahoo repurposed last year to help them deal with the consequences of spam to (and apparently from) addresses in stolen address books. Since DMARC cannot tell mail sent through complex paths like mailing lists from phishes, this had the unfortunate side effect of screwing up nearly every discussion list on the planet. Last week the DMARC group published a proposal called ARC, for Authenticated Received Chain, that is intended to mitigate the damage. What is it, and how likely is it to work? more

Why DNS is Broken, in Plain English

At ICANN's meeting in Egypt last week, I had the opportunity to try and explain to various non-technical audiences why the Domain Name System (DNS) is vulnerable to attack, and why that is important, without needing a computer science degree to understand it. Here is the summary. more

More Stepping Stones Before This Summer’s Seminal DNSSEC Events

The deployment of Domain Security Extensions (DNSSEC) has crossed another milestone this month with the publication of DURZ (deliberately unvalidatable root zone) in all DNS root servers on 5 May 2010. While this change was virtually invisible to most Internet users, this event and the remaining testing that will occur over these next two months will dictate the ultimate success of DNSSEC deployment across the Internet. more

Bruce Schneier to Speak About Internet Surveillance at IETF 88 Technical Plenary Next Week

How do we harden the Internet against the kinds of pervasive monitoring and surveillance that has been in recent news? While full solutions may require political and legal actions, are there technical improvements that can be made to underlying Internet infrastructure? As discussed by IETF Chair Jari Arkko in a recent post on the IETF blog, "Plenary on Internet Hardening", the Technical Plenary at next weeks IETF 88 meeting in Vancouver, BC, Canada, will focus on this incredibly critical issue. more

Black Hats, White Hats, Crackers and Bots

One of the other web sites I subscribe to is Stratfor. It's a global intelligence website and doesn't really have much to do with spam. But I like politics so I read it. They have some articles which you can get for free, but the better stuff you have to pay for. About two weeks ago, they ran a three-part series on Cyberwarfare. The first article was the title of this post, which you can access here (requires registration). In the article they described different types of cybercriminals and not-so-criminals which they referred to under the umbrella as "hackers." more

Unexpected Behaviour Observed With DNS Root Servers After Cryptographic Change

The DNS root servers were reported by Verisign to be under unexpected attack from name servers across the Internet following ICANN's recent changes to their cryptographic master keys. more

Equifax Breach Blamed on Open-Source Software Flaw

Equifax has blamed a flaw in the software running its online databases for the massive breach revealed last week that has allowed hackers to steal personal information of as many as 143 million customers. more

Microsoft Releases a Cybersecurity eBook, Free Download

Micorsoft has released a 253 page cybersecurity ebook primarily intended for teens but also serves as a useful resource for adults interested in overall understanding of various Internet security topics. more

Nameserver Operators Need the Ability to “Disavow” Domains

Yesterday's DDoS attack against DNSimple brought to light a longstanding need for DNS nameserver operators to have an ability to unilaterally repudiate domains from their nameservers. The domains under attack started off on DNSMadeEasy, migrated off to DNSimple and took up residence there for about 12 hours, causing a lot of grief to DNSimple and their downstream customers. more

The Top 3 Emerging Threats on the Internet

Last week at RSA, Bruce Schneier gave a talk on the top 3 emerging threats on the Internet. Whereas we in the security field usually talk about spam, malware and cyber crime, he talked about three meta-trends that all have the potential to be more dangerous than the cybercriminals. Here are my notes. more