Welcome to my blog

This is my blog on (mostly) cybersecurity, IoT and related subjects. It contains some historic stuff from LinkedIn and other places, as well as new thoughts that I’ll collect here. I’ll also occasionally talk about research work, including publications or other academic engagements.

For more information about me, visit my personal website.

In detail: SCRAM with channel binding

Visualising the process, discussing its shortcomings

In January, I asked whether TLS channel binding with strong authentication was the solution to defend against MITM or proxy style phishing attacks. The answer was “yes, but also no”. I will look beyond SCRAM soon, but first I want to fulfil a promise to go into more detail about how SCRAM works, especially with channel binding.

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Nine things I hate about Multi-Factor Authentication

My love-hate relationship with 2FA/MFA

Multi-factor authentication (MFA) is a critical part of our defence of information systems, but it is far from perfect. I’ve made a list of list of things I dislike about it, not because I think that MFA needs to go away, but because if we can solve some of these gripes, MFA becomes even more powerful. What is MFA? When I talk about MFA, I mean the authentication methods that tend to be used in addition to your username/password. [Read More]

Channel Binding: Should you be using it?

Stopping phishing in its tracks... maybe

Authentication and in particular passwords are the bugbear of many cybersecurity professionals. For all the encryption, firewalls, IDS and other defences we put in place, if authentication doesn’t do its job properly, or a user’s credentials get stolen, a compromise is very likely. In the future, we might embrace password-less authentication, relying instead on biometrics, tokens and smart devices in various combinations. Indeed, some platforms do this already, but not all. [Read More]

VPNs Considered Harmful

Confusion between anonymising and corporate VPNs is bad for cybersecurity

The Virtual Private Network, or VPN, has become a familiar term amongst Internet users in recent years. Yet, the secure tunnelling technology has been around much longer. So, why is it popular now, why should this be considered harmful, and what do we do about it? Take the global Google Trends for the terms VPN, SSL and TLS, pictured below. Comparatively few people seem to care about SSL and TLS, but VPN sees growing interest, with repeated spikes. [Read More]

Meep Meep! A story of certificate (un)verification πŸ”πŸ“œπŸ”βŒ

ACME clients seldom check the certificates they receive

This article discusses the lack of certificate checking done by ACMEv2 clients, as well as the lack of provision in the ACMEv2 protocol specification to encourage any checking. This article explores the implications of this, and demonstrate why we should probably being doing some additional checks in our ACMEv2 clients. The project is called “Meep Meep”, because that’s the sound a roadrunner makes. The author couldn’t think of a cleverer name for something related to ACME. [Read More]