Ubuntu: enable the firewall and manage it with UFW

In this tutorial, I will explain how to activate the firewall on a computer with Ubuntu and manage it with UFW. UFW for Uncomplicated Firewall is a simplified Netfilter command line utility, it is a simple alternative to iptables, which allows to manage firewall rules. If UFW is not installed, use the following command to …

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Windows Server: disable a cipher suite

In this tutorial, I will walk you through how to disable a cipher suite also call cipher. If you arrive on this tutorial by a search engine, there is a good chance that it is due to a vulnerability test and that you have an alert that goes up because vulnerable cryptographic suites (cipher) are …

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Crowdsec: protecting Windows servers

In a previous tutorial, I explained how to protect your Linux servers with Crowdsec in order to block “malicious” traffic. For almost 2 months now, the Crowdsec version has been available for Windows. If you are not yet familiar with Crowdsec, here is a brief presentation: Crowdsec will analyze different log files (Web, firewall, SSH, …

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Active Directory: change the KrbTgt account password

In this tutorial, I will explain how to change the password of the KrbTgt account. Before explaining how to change the password of this account, I will give you some explanations. Who is krbtgt? The krbtgt account is a disabled service account in the Active Directory, which is used for the distribution of Kerberos Tickets, …

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Active Directory: Secure Domain Join to Domain Admins

In this tutorial, we will address a security point on an Active Directory environment, which is the domain joining of computers. What you need to know (some administrators don’t know this), all domain users can join a computer to a domain, they can even join up to 10 computers. Domain administrators have no limit as …

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Active Directory: harden the security of your environment

In this tutorial dedicated to Active Directory and security, I will give you some tips to harden the level of security in order to be less vulnerable to attacks. The different configuration points, which will be discussed, simply allow attacks to be made more difficult and longer internally, in no way will they guarantee that …

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GPO: disabled SMBv1

In this tutorial, I will walk you through how to disable SMBv1 support add-on using Group Policy. To disable full SMBv1 support, you must act on the two SMB components which are: The server who is the one who shares The client that allows the use of shared resources. Disabling by group policy is done …

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