Linux Tutorials on the topic “security”
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Setting Up ProFTPd + TLS On Debian Etch
Author: Falko Timme •
Tags: debian, ftp, security •
Comments: 8 Setting Up ProFTPd + TLS On Debian Etch FTP is a very insecure protocol because all passwords and all data are transferred in clear text. By using TLS, the whole communication can be encrypted, thus making FTP much more secure. This article explains how to set up ProFTPd with TLS on a Debian Etch server.
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HowTo: Install And Configure FWKNOP (Using EnGarde Linux)
Author: secureguardian • Tags: security • Comments: 0HowTo: Install And Configure FWKNOP (Using EnGarde Linux) Secret knocks have been used for purposes as simple and childish as identifying friend or foe during a schoolyard fort war. Fraternities teach these knocks as a rite of passage into their society, and in our security world we can implement this layer of security to lock down an SSH server. The FireWall KNock Operator (fwknop) is an excellent port knocking implementation that combines encrypted port knocking with passive OS finger-printing. This makes it possible to define specifically which Linux systems are allowed access to your SSH server. fwknop combines its functionality with iptables rules and log messages to grant or deny access to the SSH daemon.
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Adding And Updating SpamAssassin Rulesets With RulesDuJour
Author: Falko Timme • Tags: antivirus, linux, security • Comments: 2Adding And Updating SpamAssassin Rulesets With RulesDuJour This article explains how you can download additional SpamAssassin rulesets resp. automatically update these rulesets with a shell script called RulesDuJour. These additional rulesets can increase your spam recognition rate dramatically. Most of the rulesets that RulesDuJour supports can be found on the SA Rules Emporium web site.
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Intrusion Detection: Snort, Base, MySQL, And Apache2 On Ubuntu 7.10 (Gutsy Gibbon)
Author: DevilMan • Tags: security, ubuntu, monitoring • Comments: 6Intrusion Detection: Snort, Base, MySQL, and Apache2 On Ubuntu 7.10 (Gutsy Gibbon) In this tutorial I will describe how to install and configure Snort (an intrusion detection system (IDS)) from source, BASE (Basic Analysis and Security Engine), MySQL, and Apache2 on Ubuntu 7.10 (Gutsy Gibbon). Snort will assist you in monitoring your network and alert you about possible threats. Snort will output its log files to a MySQL database which BASE will use to display a graphical interface in a web browser.
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Virtual Users And Domains With Postfix, Courier And MySQL (Ubuntu 7.10)
Author: Falko Timme • Tags: antivirus, postfix, security, ubuntu • Comments: 5Virtual Users And Domains With Postfix, Courier And MySQL (Ubuntu 7.10) This document describes how to install a mail server based on Postfix that is based on virtual users and domains, i.e. users and domains that are in a MySQL database. I'll also demonstrate the installation and configuration of Courier (Courier-POP3, Courier-IMAP), so that Courier can authenticate against the same MySQL database Postfix uses. The resulting Postfix server is capable of SMTP-AUTH and TLS and quota (quota is not built into Postfix by default, I'll show how to patch your Postfix appropriately). Passwords are stored in encrypted form in the database (most documents I found were dealing with plain text passwords which is a security risk). In addition to that, this tutorial covers the installation of Amavisd, SpamAssassin and ClamAV so that emails will be scanned for spam and viruses.
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Full Mail Server Solution w/ Virtual Domains & Users (Debian Etch, Postfix, Mysql, Dovecot, DSpam, ClamAV, Postgrey, RBL)
Author: Vecter • Tags: antivirus, debian, mysql, postfix, security • Comments: 5Full Mail Server Solution w/ Virtual Domains & Users (Debian Etch, Postfix, MySQL, DoveCot, DSpam, ClamAV, Postgrey, RBL) This guide describes how to set up a full email solution in Debian Linux (all code is from Debian Etch). I was asked to design a secure, scalable, portable solution for a small company. While the guide references many 'servers', the company only had 4 physical machines, Xen was used to virtualize the entire solution. That particular aspect of the system is not discussed in this guide, although I will try to get it into the next revision.
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Chrooted SSH/SFTP On Fedora 7
Author: o.meyer • Tags: fedora, security • Comments: 6Chrooted SSH/SFTP On Fedora 7 This document describes how to set up a chrooted SSH/SFTP environment on Fedora 7. The chrooted users will be jailed in a specific directory where they can't break out. They will be able to access their jail via SSH and SFTP.
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Preventing Brute Force Attacks With Fail2ban On OpenSUSE 10.3
Author: Falko Timme • Tags: security, suse • Comments: 4Preventing Brute Force Attacks With Fail2ban On OpenSUSE 10.3 In this article I will show how to install and configure fail2ban on an OpenSUSE 10.3 system. Fail2ban is a tool that observes login attempts to various services, e.g. SSH, FTP, SMTP, Apache, etc., and if it finds failed login attempts again and again from the same IP address or host, fail2ban stops further login attempts from that IP address/host by blocking it with an iptables firewall rule.
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Preventing Brute Force Attacks With BlockHosts On Debian Etch
Author: Falko Timme • Tags: debian, security • Comments: 6Preventing Brute Force Attacks With BlockHosts On Debian Etch In this article I will show how to install and configure BlockHosts on a Debian Etch system. BlockHosts is a Python tool that observes login attempts to various services, e.g. SSH, FTP, etc., and if it finds failed login attempts again and again from the same IP address or host, it stops further login attempts from that IP address/host. By default, BlockHosts supports services that use TCP_WRAPPERS, such as SSH, i.e. services, that use /etc/hosts.allow or /etc/hosts.deny, but it can also block other services using iproute or iptables.
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Chrooted SFTP With MySecureShell On Debian Etch
Author: Falko Timme •
Tags: debian, security •
Comments: 5 Chrooted SFTP With MySecureShell On Debian Etch This tutorial shows how to install MySecureShell on a Debian Etch system. MySecureShell is an SFTP server that is based on OpenSSH and can be configured in many ways, e.g. it has support for chrooting users into their homedirs or for limiting upload-/download bandwidths. MySecureShell makes SFTP available for users that do not have shell access so that these users do not have to use the insecure FTP protocol anymore.
