Deny lists

Identify vulnerabilities before attackers exploit them. A list of malicious (phishing) domains for enhanced IT protection, provided by the experts at CSIRT.CZ.

Get a quote

We care about your safety

Deny lists are a security tool that provides a systematically updated list of malicious domains designed to protect against phishing, malware distribution, investment scams, and fake online stores. These lists utilize data from automated tools as well as analyses by the national security team CSIRT.CZ. Thanks to their specific knowledge of the Czech environment, they also detect threats that automated tools might overlook.



The added value of our Deny Lists lies in the fact that they are regularly reviewed and maintained by experts from the national security team, who have more than 15 years of experience in resolving security incidents.

2 000+

blocked URLs
every month

500 000~

users protected
by experts from CSIRT.CZ

90 000

total blocked
domain names

40+

data sources from which
the data is drawn

Main advantages

Localized protection

DNS hosting on an anycast infrastructure built for the .CZ national domain and designed with an emphasis on maximum robustness, high capacity, diversity, and coverage not only within the Czech Republic and Europe, but also on all other continents. There is no more robust DNS infrastructure in the Czech Republic.

Flexible management of blocked domains

Each customer can use the web interface to manage the list of blocked domains on their own. This allows them to add their own domains that they wish to block or, conversely, ensure that certain domains are not blocked if the situation requires it.

We are actively seeking new sources

We are constantly improving our service and seeking new sources of information about malicious domains. Our goal is to offer Czech users, businesses, and institutions the best possible protection against targeted attacks.

Unique data

The analytical work of CSIRT.CZ provides us with unique data, which we obtain by combining multiple time-tested CSIRT.CZ projects and by connecting to other significant sources.

Part of the requirements of the ISO 27001 standard

Protecting users from dangerous websites is now considered just as important as antivirus protection. Web filtering has therefore been included in the latest version of the ISO 27001 standard. Our service will help you meet one of the requirements of this standard.

Easy integration

Deny lists are designed to be easily integrated into your existing environment. All you need is to run your own recursive DNS server. If you don't have one, we can set one up for you.

Solutions tailored to your needs

  • Phishing Protection

  • Secure Network

  • Analytical Accuracy

  • Easy Integration

  • Localized Protection

Frequently asked questions

Reference

Get a quote

Kateřina Chmelová
Director of Sales

katerina.chmelova@nic.cz
+420 724 125 565

I would like to know more

By clicking on the "Send inquiry" button, you hereby confirm that CZ.NIC will process your personal data in accordance with our Privacy policy .