applied security research

About Zolder

Welcome to Zolder! We started this company in March 2020. With 4 fellows, sharing a decent amount of experience as cybersecurity professionals, we have set course to build a great and indefinite working environment for hackers. Because that is who we are, and we believe the availability of hacking skills will be paramount for succesful digital societies.

From Zolder we provide help through security services and software to companies.

Currently we are working on a platform to assess and monitor cloud infrastructure like Microsoft 365. Our goal is to provide SMB with a security governance tool that will match their needs. It will allow us to help a large set of customers with insights we get from our own security research efforts.

Furthermore today we provide time-based services on-demand, like security testing services (e.g. penetration testing), give lectures and presentations as well as training. Let us know what you need, we can probably help out. Contact us through social media or contactform.

Currently, as we are doing fundamental work in setting up our business, we focus on our local business. Therefore most content you will find here will be in Dutch. However, we do post and speak in English every now and then.

Please follow us on social media to stay up to date.


Story

In a dynamic society – in which the digitization of the world around us is increasingly being implemented through robotization, virtual reality, and IoT (Internet of Things) – the social need for a knowledge safety net to carry out that digitization in a controlled fashion is growing. Especially now that the developments and uncertainties related to the COVID-19 crisis show that more and more organizations are storing their data in the cloud, and video conferencing has taken off. Applied digital security research is crucial to create protection for organizations that want to be well prepared for all the technological possibilities the future offers.

Analytical thinking of professional hackers, cyber researchers, software developers, and security consultants is necessary to find solutions to security issues that may not yet exist or that do not present a direct problem. The specialisms required to perform this applied security research have now been brought together under one roof: Zolder.

The real ‘diehard’ cybersecurity experts have learned the tricks of the trade in their attic room. That attic room mentality stands for technical craftsmanship and love for cybersecurity. Zolder was founded as a company based on a deep-rooted passion for all developments related to security in the digital domain. The four founders (Rik van Duijn, Wesley Neelen, Theo Snelleman, and Erik Remmelzwaal), who have met each other as direct colleagues at DearBytes/KPN Security, can always be woken up for a security challenge.

The Zolder team mainly wants to create a company that forms a foundation for security work. Together, Rik, Theo, Erik, and Wesley have over thirty years of work experience in various domains of cybersecurity research. The four have specific hacking, malware, reverse engineering, data analysis, and IT management skills. Customers can rely on their in-depth digital knowledge: from the basics of electrical engineering to networking, operating systems, and applications, incident response in case of virus outbreaks and strategic development of both security hardware and software.

The main goal of the four at Zolder is to be able to conduct autonomous and pragmatically applied security research for parties who need it. Because a substantial part of the Dutch business community is already transforming and implementing digitization processes, it is extremely important from a social perspective that security professionals think about how we can safely adopt the digital technology of the future. Zolder responds to this need by using all jointly accumulated knowledge and experience in the development of new technology. This offers digital protection for all technological possibilities and challenges of the future. It is especially important to invest as much time as possible in research and in this way to convert all knowledge and capacity into value for customers and society in general. Ultimately, the Zolder mentality is characterized by being big and strong, precisely by staying small and operating smartly.

Blogs

Hacking my Helium Crypto Miner

Wesley Neelen - 05 sep 2022
Recently I came across an interesting cryptocurrency project called Helium. Its a wireless network built by people all around the world. The people that help expanding the network by adding a hotspot receive the Helium cryptocurrency coin by providing the coverage. During my research I decided to order one of those Helium miners. I ordered […] Lees verder

PEN-300 / OSEP review

Wesley Neelen - 19 jul 2022
This year I decided to start a new study, the PEN-300 course of Offensive Security. In 2012 I did the OSCP course and in 2013 OSCE. In 2016 I took the OSEE class in Vegas, unfortunately never took the exam (one of my biggest mistakes ever🥴). I liked all the courses very much at that […] Lees verder

Deze 3 misverstanden blokkeren het ontwikkelen van cyberweerbaarheid

Zolder B.V. - 04 jul 2022
Het NCTV heeft weer het jaarlijkse Cybersecuritybeeld Nederland gepubliceerd. Het CSBN-2022. Mooie aanleiding om eens op te schrijven waar ik al langer mee in mijn hoofd zit. Drie hardnekkige en foute aannames die mensen hebben bij digitale dreigingen. Drie misverstanden dus, die in mijn ervaring de belangrijkste reden zijn dat we nauwelijks vooruit komen met […] Lees verder

Cyberweerbaarheid en Operational Technology

Erik Remmelzwaal - 02 jun 2022
Onlangs nam Erik Remmelzwaal, co-owner en Managing Director van Zolder BV, deel aan een tafelgesprek van Data Value Center – Smart Industry (DVC-SI). Het thema was Cyberweerbaarheid en Operational Technology, en het gesprek werd opgenomen in de campus van Breda Robotics, waar Zolder lid van is. De opname is inmiddels beschikbaar en terug te kijken […] Lees verder

Detecting MFASweep using Azure Sentinel

Zolder B.V. - 01 nov 2021
Many companies are using cloud services such as Microsoft 365 for email, file sharing and communicating. If an attacker gains access to valid credentials that allows them to authenticate to the account, all information within the account is usually instantly accessible. Therefor, implementing multi factor authentication is one of the most important steps while securing […] Lees verder

Public SharePoint sites - the new open shares

Wesley Neelen - 16 sep 2021
During one of our engagements we were investigating a Microsoft 365 environment. My colleague Rik discovered that many SharePoint sites were publicly available within the organization. We were surprised by the amount sites that were wide open this way. A lot of sensitive information was located on those sites, for example PII-information and passwords for […] Lees verder

Decrypt passwords from Xerox Workcentre config backups

Rik van Duijn - 29 aug 2021
During a recent engagement we encountered Xerox WorkCentre printers using default credentials (admin:1111). Usually it’s just another finding, but this time we noticed the printer had SMB and e-mail credentials configured. For LDAP we usually point the printer to our own IP and get access to the plaintext creds that way. But in the case […] Lees verder

Office 365 audit logging

Rik van Duijn - 19 aug 2021
It’s important to enable audit logging for o365 even if you are not monitoring them actively. Atleast if you get hacked there’s logging to investigate :). The audit log is not always enabled by default, it seems to rely on license levels. However there are some important things to take into consideration. You can enable […] Lees verder

Ransomware, nationale crisis?

Erik Remmelzwaal - 04 aug 2021
Als er 1 digitale dreiging is die veel in het nieuws komt, dan is het ransomware. Er wordt zelfs gesproken van een nationale crisis. Lees verder

Mijlpalen en hoe het gaat

Zolder B.V. - 02 jul 2021
Vandaag gebeurden er op Zolder toch een paar dingen die blogwaardig zijn. Dus prima aanleiding om nog maar eens de laptop open te klappen en te vertellen hoe het gaat. Nieuwe collega’s Het is 1 juli 2021 en we zijn ruim een jaartje onderweg als Zolder. De belangrijkste stap die we vandaag zetten, is dat […] Lees verder

Zolder wordt hoofdsponsor HCZ

Zolder B.V. - 01 jul 2021
Vandaag is bekend geworden dat Zolder de nieuwe hoofdsponsor is van HCZ – Hockeyclub Zevenbergen. De komende drie seizoenen zal het logo van Zolder daarom voorop de shirts van alle HCZ leden prijken. We zijn heel erg trots op deze nieuwe stap voor ons jonge bedrijf, en hopen zo de relatie met onze regio te […] Lees verder

Breda Robotics

Erik Remmelzwaal - 10 mei 2021
Zolder BV is toegetreden tot het netwerk van Breda Robotics. Deze vereniging brengt organisaties bij elkaar die actief zijn rondom robotisering in de regio West-Brabant. Voor Zolder geeft Breda Robotics de mogelijkheid om samen te werken met de robotiseringsindustrie. Te begrijpen hoe die sector precies werk en op welke vlakken cybersecurity kennis kan worden ingezet […] Lees verder

27% .nl domeinen slecht beschermd tegen spoofing

Erik Remmelzwaal - 29 apr 2021
TLDR: We scanden de DNS records van 1,6 miljoen .nl domeinen en vonden uit: 9% is rechtstreeks gekoppeld aan Microsoft 365, daarmee is Microsoft veruit de grootste Google is nr2 en heeft 4% van de domeinen aan zich verbonden, nagenoeg gelijk aan een aantal andere spelers. Van alle mail-enabled domeinen heeft 27% geen SPF record […] Lees verder

Zolder biedt MKB betaalbare en eenvoudige security-app

Zolder B.V. - 12 apr 2021
“Attic voorkomt dat security een luchtbel wordt” Security is bij mkb-bedrijven vaak het ondergeschoven kindje. Ze hebben er de mensen en het budget niet voor. Dat maakt deze doelgroep een aantrekkelijk doelwit voor cybercriminelen. Voor de vier doorgewinterde cybersecurity-experts van start-up Zolder reden om Attic te introduceren. Deze eenvoudige, goedkope en toekomstbestendige app maakt mkb’ers […] Lees verder

Nieuwe Themesong voor Zoldersessions

Erik Remmelzwaal - 13 mrt 2021
Ik vond het tijd worden voor een nieuw liedje voor onze Zoldersessions. Tot nu toe hadden we er een rechtenvrij liedje onder staan, namelijk EVA_失望した, maar wilden toch iets meer 'eigens'. Daar schakelden we Bjørgen van Essen voor in met dit eindresultaat. Dit is hoe dat tot stand kwam. Lees verder

Zolder.App Open Beta

Zolder B.V. - 02 feb 2021
We launched the final beta release to the Google and Apple appstores. Any business running on Microsoft 365 is more than welcome to join. As a beta-tester you will receive a free subscription to the Zolder.App Premium Plan for the remainder of the beta phase, which is scheduled to run through April 30th 2021. Zolder.App […] Lees verder

GGD data is topje van ijsberg

Erik Remmelzwaal - 26 jan 2021
Maandag kwam RTL Nieuws, na onderzoek van Daniël Verlaan, naar buiten met het nieuws dat gestolen data van de GGD online wordt verhandeld door criminelen. Het gaat om data die onderdeel uitmaakt van het bron- en contactonderzoek dat de GGD uitvoert als onderdeel van de bestrijding van Corona/COVID-19. De data bevat gevoelige persoonsgegevens en criminelen […] Lees verder

#CES2021 - We Are Ready!

Erik Remmelzwaal - 06 jan 2021
We are very excited to be part of the #CES2021NL mission! Meet us at CES (Januari 11-14) in our online booth 10609 and see how we solve global challenges with NLTech. Erik Remmelzwaal, Co-Founder & CEO Yes I indeed think we are ready for CES. At this virtual event we will showcase Zolder.App. I am […] Lees verder

Zolder.App Blog 3 - Feedback

Erik Remmelzwaal - 27 nov 2020
Bij het ontwikkelen van een nieuwe dienst, zeker als dit Software-as-a-Service betreft, is feedback vanuit (potentiële) afnemers cruciaal. In het geval van Zolder.App is de doelgroep het MKB. We zijn al gelijk na lancering van het merk Zolder gestart met het vinden van MKB-ers die als tester wilden helpen. Oproep 19-apr-2020 Dit leidde tot best […] Lees verder

Azure App Consent Policies

Rik van Duijn - 11 nov 2020
OAuth consent phishing has been on the rise for a while now. Unsurprisingly, Microsoft has gradually introduced measures to protect from this type of attack. Latest: Risk-Based Step-Up Consent. Lees verder