Kerberos made easy

Kerberos is an authentication protocol that works on the basis of tickets that allows clients to connect to services over an insecure network and still allow clients to prove their identity in a secure manner.

The steps described below are a compilation of what I found when reading on Kerberos. Feel free to share your comments!

These are the steps necessary for a client to obtain an authenticated and verified request to a service (forRead more.

What could have limited the impact of the WannaCry / Wcry / WannaCrypt ransomware?

A major wave of ransomware called WannaCry / Wcry / WannaCrypt has hit many organizations around the world, causing panic among many users, system administrators and security professionals. The details of the ransomware have been covered in detail at other posts

Everything you need to know about the WannaCry / Wcry / WannaCrypt ransomware Player 3 Has Entered the Game: Say Hello to ‘WannaCry’ Massive outbreak of ransomware variant infects large amounts of computers aroundRead more.

Simplifying Risk Management

I published an article on IBM Security Intelligence on Simplifying Risk Management.

What is Shodan telling us about ICS in Belgium?

I have been using Shodan, “the world’s first search engine for Internet-connected devices”, since a long time. Recently I switched my free account to a membership account. A membership account allows you to do API queries with additional query filters (for example restricting search results to specific countries).

In this post I describe the results of querying the Shodan API for ICS (or related) devices in Belgium. These results are entirely based on what isRead more.

Submit malware samples to VMRay via MISP

I’m a happy user of MISP, Malware Information Sharing Platform & Threat Sharing. MISP core already contains a lot of features to satisfy your needs when it concerns threat and information sharing. But there’s always room for improvement. If you submit a feature request, MISP can be extended with your request. However changing the core is not always desirable. Also sometimes you want some feature to work just the way you want it, this doesn’tRead more.

The Krebs Attack: Sign Of A Game Changer

I published an article on The Krebs Attack: Sign Of A Game Changer on the Ipswitch blog.

This article lists the new wave of large scale DDoS attacks against KrebsOnSecurity and OVH and how the release of the Mirai botnet source code can leverage new attacks. I describe how this influences the risks you have to take into account when protecting your infrastructure.

Proxy server logs for incident response

When you do incident response having access to detailed logs is crucial. One of those treasure troves are proxy server logs.

Proxy server logs contain the requests made by users and applications on your network. This does not only include the most obvious part : web site request by users but also application or service requests made to the internet (for example application updates).

Ideally you have a transparent proxy, meaning that all outgoing requestsRead more.

Malware scanning of web directories with OWASP WebMalwareScanner

One of the recent incidents I had to handle involved a compromised webhost. This allowed me to do some Exploring webshells on a WordPress site. In the aftermath of the investigation I searched for tools that could have improved my tasks (evaluating which files might have been compromised).

One of the approaches I had in mind was take a hash of every file and then verify that hash with Virustotal. This would have worked inRead more.

Using Bro for building Passive DNS data

Passive DNS describes an historical database of DNS resolutions. I’ve written a previous post on Using Passive DNS for Incident Response, more specifically combining it with Moloch.

If you run your own corporate -internal- nameservers it makes sense to monitor what domains have been queried and what results were returned in the past. You can use the collection of internal queries for future incident response. You can use this collected information to cross-check with informationRead more.

Use Certificate Transparency for OSINT and passive reconnaissance

SANS ISC recently posted an article on The Dark Side of Certificate Transparency.

Certificate transparency means that participating certificate authorities will publish all certificates that they issue in a log. This information is public, meaning that you can search it at will.

The article already touches one of the side effects of having this information publicly available. By publishing the information organizations can disclose hostnames they’d rather not be known on the internet.

There areRead more.