Security Issues and Poptop

PPTP does not have the best history in terms of security. The original Microsoft implementation for PPTP faired very poorly. MS-CHAPV2 solved these weaknesses - for wired networks. Unfortunately, back in 2004, Joshua Wright released a version of ASLEAP capable of brute-force attacking PPTP passwords in a wireless environment. As a systems administrator for the VPN, you can't tell if a user is connecting via some public WiFi service where someone might be running a tool like ASLEAP. Yet, the presense of PPTP client software on Windows machines makes using PPTP very tempting. The best answer to this problem is to utilize two-factor authentication. If a one-time passcode is brute-forced, it won't matter as it can't be used again.

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How To Check If Your Server Is Infected With The Linux/Rst-B Backdoor (Debian Etch)

Linux Rst-B is a backdoor that can be used to add your server to botnets (see http://www.heise.de/newsticker/meldung/103563 (in German)). This short guide explains how you can install and use the Sophos Linux/RST-B detection tool to check your Debian Etch server and find out if it is infected with Linux Rst-B.

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Meet the Anti-Nmap: PSAD (EnGarde Secure Linux)

Having a great defense involves proper detection and recognition of an attack. In our security world we have great IDS tools to properly recognize when we are being attacked as well as firewalls to prevent such attacks from happening. However, certain attacks are not blindly thrown at you - a good attacker knows that a certain amount of reconnaissance and knowledge about your defenses greatly increases the chances of a successful attack. How would you know if someone is scanning your defenses? Is there any way to properly respond to such scans? You bet there is...

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Intrusion Detection: Snort (IDS), OSSEC (HbIDS) And Prelude (HIDS) On Ubuntu Gutsy Gibbon

Everybody knows the problem, you have a IDS tool(s) installed and every tool has his own interface. Prelude will allow to log all of the events to the prelude database and be consulted using one interface (prewikka). This howto will describe how to install and configure the different tools that will make up the complete solution.

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How to install the WiKID Strong Authentication Server - Community Edition

The WiKID Strong Authentication Server is a dual-source two-factor authentication system. PINs are encrypted on a software token and sent to the WiKID server. If the PIN is correct, the encryption valid and the account active, a one-time password is generated, encrypted and returned to the user's token where it is decrypted and presented for use with a network-based services. While there are a number of tutorials on how to combine WiKID's two-factor system a variety of systems (such as SSH, OpenVPN, Apache and SSL-VPNs), this is the first to address how to install the WiKID Server.

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How To Implement Domainkeys In Postfix Using dk-milter

Domainkeys is "DomainKeys is a method of e-mail authentication. Unlike some other methods, it offers almost end-to-end integrity from a signing to a verifying Mail Transfer Agent (MTA). In most cases the signing MTA acts on behalf of the sender, and the verifying MTA on behalf of the receiver. DomainKeys is specified in Historic RFC 4870, which is obsoleted by Standards Track RFC 4871, DomainKeys Identified Mail (DKIM) Signatures." according to the wikipedia. So why a how to on it when there is DKIM ? Well domainkeys is still actively being used and is more widely deployed than DKIM, the developer Yahoo still uses it to sign and verify mail although they are contributers to the DKIM standard.

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Set Up Postfix DKIM With dkim-milter

DKIM is an authentication framework which stores public-keys in DNS and digitally signs emails on a domain basis. It was created as a result of merging Yahoo's domainkeys and Cisco's Identified Internet mail specification. It is defined in RFC 4871.

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Becoming Root User Without Password In GNU/Linux Ubuntu

Ubuntu has an excellent security tool called sudo that allows the administrator to delegate control of certain commands to certain users. But to use it you must type the sudo word before any command, and validate (and confirm) it with your system account password.

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Install Firebird 2.0.3 Database Server On Ubuntu 7.10

This tutorial explains how you can install the Firebird database server (version 2.0.3) on an Ubuntu 7.10 server.

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Back Up Your Files With Fwbackups On Fedora 8

This document describes how to set up, configure and use Fwbackups on a Fedora 8 desktop. The result is an easy-to-use backup system for desktop usage. Fwbackups creates partial backups which can be stored locally or on a removable device. You have also the option to run scheduled backups.

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The XO laptop (of the One-Laptop-Per-Child initiative) is an inexpensive laptop project intended to help educate children around the world. The laptop includes many innovations, such as a novel, inexpensive, and durable hardware design and the use of GNU/Linux as the underlying operating system. The XO also includes an application environment written in Python with a human interface called Sugar, accessible to everyone (including kids). This article is excerpted from the developerWorks tutorial "Application development for the OLPC laptop," which takes a look at the Sugar APIs and shows how to develop and debug a graphical activity in Sugar using Python.
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A typical UNIX or Linux machine creates many log files during the course of its operation. Some of these contain useful information; others can be used to help you with capacity and resource planning. This article looks at the fundamental information recorded within the different log files, their location, and how that information can be used to your benefit to work out what is going on within your system.
Read more..

Security Issues and Poptop

PPTP does not have the best history in terms of security. The original Microsoft implementation for PPTP faired very poorly. MS-CHAPV2 solved these weaknesses - for wired networks. Unfortunately, back in 2004, Joshua Wright released a version of ASLEAP capable of brute-force attacking PPTP passwords in a wireless environment. As a systems administrator for the VPN, you can't tell if a user is connecting via some public WiFi service where someone might be running a tool like ASLEAP. Yet, the presense of PPTP client software on Windows machines makes using PPTP very tempting. The best answer to this problem is to utilize two-factor authentication. If a one-time passcode is brute-forced, it won't matter as it can't be used again.

Read more...
Read more..

Server Monitoring With munin And monit On Mandriva 2008.0

In this article I will describe how you can monitor your Mandriva 2008.0 server with munin and monit. munin produces nifty little graphics about nearly every aspect of your server (load average, memory usage, CPU usage, MySQL throughput, eth0 traffic, etc.) without much configuration, whereas monit checks the availability of services like Apache, MySQL, Postfix and takes the appropriate action such as a restart if it finds a service is not behaving as expected. The combination of the two gives you full monitoring: graphics that lets you recognize current or upcoming problems (like "We need a bigger server soon, our load average is increasing rapidly."), and a watchdog that ensures the availability of the monitored services.

Read more...
Read more..

Becoming Root User Without Password In GNU/Linux Ubuntu

Ubuntu has an excellent security tool called sudo that allows the administrator to delegate control of certain commands to certain users. But to use it you must type the sudo word before any command, and validate (and confirm) it with your system account password.

Read more...
Read more..

Install Firebird 2.0.3 Database Server On Ubuntu 7.10

This tutorial explains how you can install the Firebird database server (version 2.0.3) on an Ubuntu 7.10 server.

Read more...
Read more..

Back Up Your Files With Fwbackups On Fedora 8

This document describes how to set up, configure and use Fwbackups on a Fedora 8 desktop. The result is an easy-to-use backup system for desktop usage. Fwbackups creates partial backups which can be stored locally or on a removable device. You have also the option to run scheduled backups.

Read more...
Read more..

The XO laptop (of the One-Laptop-Per-Child initiative) is an inexpensive laptop project intended to help educate children around the world. The laptop includes many innovations, such as a novel, inexpensive, and durable hardware design and the use of GNU/Linux as the underlying operating system. The XO also includes an application environment written in Python with a human interface called Sugar, accessible to everyone (including kids). This article is excerpted from the developerWorks tutorial "Application development for the OLPC laptop," which takes a look at the Sugar APIs and shows how to develop and debug a graphical activity in Sugar using Python.
Read more..

A typical UNIX or Linux machine creates many log files during the course of its operation. Some of these contain useful information; others can be used to help you with capacity and resource planning. This article looks at the fundamental information recorded within the different log files, their location, and how that information can be used to your benefit to work out what is going on within your system.
Read more..

Security Issues and Poptop

PPTP does not have the best history in terms of security. The original Microsoft implementation for PPTP faired very poorly. MS-CHAPV2 solved these weaknesses - for wired networks. Unfortunately, back in 2004, Joshua Wright released a version of ASLEAP capable of brute-force attacking PPTP passwords in a wireless environment. As a systems administrator for the VPN, you can't tell if a user is connecting via some public WiFi service where someone might be running a tool like ASLEAP. Yet, the presense of PPTP client software on Windows machines makes using PPTP very tempting. The best answer to this problem is to utilize two-factor authentication. If a one-time passcode is brute-forced, it won't matter as it can't be used again.

Read more...
Read more..

Server Monitoring With munin And monit On Mandriva 2008.0

In this article I will describe how you can monitor your Mandriva 2008.0 server with munin and monit. munin produces nifty little graphics about nearly every aspect of your server (load average, memory usage, CPU usage, MySQL throughput, eth0 traffic, etc.) without much configuration, whereas monit checks the availability of services like Apache, MySQL, Postfix and takes the appropriate action such as a restart if it finds a service is not behaving as expected. The combination of the two gives you full monitoring: graphics that lets you recognize current or upcoming problems (like "We need a bigger server soon, our load average is increasing rapidly."), and a watchdog that ensures the availability of the monitored services.

Read more...
Read more..