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Welcome!

I’m Koen . I live in Bruges (Belgium), a splendid medieval city also known as the Venice of the North.

I’m involved with computer security and I work as a member of a CERT (Computer Emergency Response Team).

I’m available as a freelancer (cudeso.be) -provided the freelance jobs do not interfere with my day-to-day job- for web-application development (Drupal, WordPress, Joomla and PHP applications), as a system administrator (OpenBSD and Linux mostly) and for all computer security related tasks.

My main interests in computers are security, web applications (PHP, MySQL, Apache), system administration and free software.

This site hosts a blog and I have a photo collection at Flickr.

I also have a site with (outdated) Linux information.

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Latest posts

Will Blockchain Technology Replace Traditional Business Models?

I had to brush up my knowledge on the blockchain technology and decided to write a piece about it on the SecurityIntelligence.com website : Will Blockchain Technology Replace Traditional Business Models?

The article contains a short introduction on what the blockchain technology is and how it works. I conclude with some remarks how blockchain technology could remove the middleman (banks, etc.) for financial transactions.

Whitelist e-mails in Gmail (for example MISP notifications)

Recently I noticed that some of the MISP notification e-mails ended up in my spam folder. I use Gmail linked to my personal domain.

You might argue that processing MISP mails, potentially containing restricted information, via Gmail is a problem. The MISP notifications however are GPG-encrypted so this limits a potential problem.

Whitelisting e-mails in Gmail is not limited to MISP only but I cover this use-case as it caused me some annoyances.

The firstRead more.

HTTP 304 and Apache sinkhole

This is a short post, put here as a “reminder to self” on browser caching.

A colleague recently set up an HTTP sinkhole with Apache. The setup redirected all the user requests to one specific resource.

When deploying the sinkhole, the web server logs showed that the first requests where logged with HTTP status code 200 (“OK”). The next requests however were logged with HTTP status code 304 (“Not Modified”).

The HTTP 304 code basicallyRead more.

Security Training for Incident Handling: What Else Is Out There?

I had a guest post published on Security Training for Incident Handling: What Else Is Out There?.

This post is a follow-up to an earlier post (Security Training for Incident Handlers: What’s Out There?) that points out some alternatives for training for incident handlers.

Proper Script Management: A Practical Guide

I had a guest post published on Proper Script Management: A Practical Guide.

The post lists some best practices when developing your scripts and how to measure the performance of your scripts.