Databases, Systems & Networks

POSIX Access Control Lists (ACLs) are more fine-grained access rights for files and directories. An ACL consists of entries specifying access permissions on an associated object. ACLs can be configured per user, per group or via the effective rights mask.

These permissions apply to an individual user or a group, and use the same as rwxfound in regular permissions.

For an explanation of rwx, see FilePermissions

Enabling ACLs in the Filesystem

Before beginning to work with ACLs the file system must be mounted with ACLs turned on. This can be done in /etc/fstab for the changes to be permanent.

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Plug-ins

Our job as WordPress users (aside from contributing to the WordPress community) is keeping our installs safe from people we do not want to access our sites. There are numerous plug-ins to help shore up our WordPress defenses such as Login LockDown which records IP address and blocks them after a set number of login attempts which helps against brute force attacks. Lire la suite…

source: fail2ban.org

Using geolocation to locate your attackers.

I use fail2ban on my servers to protect them from would-be attackers, if you don’t your either insanely nieve to the fact that somebody wants in your system, or your just wanting to see if you can get hacked. Most of the attackers I would assume are just after another « bot » in their « net », or maybe a place to host files.

Durzo hosts a script that allows you to log the attacks on you into a mysql database with geocoding, I thought this would be cool to use as I could see from where I was being attacked. I then got this working and another script to display the table in a web page so I could view the data easily.

I then found some scripts from Google to pull data from MySQL in a geolocation table and generate an XML file used to import into Google Maps. With some tweaking and customizing, I now have a map with the geolocation data as markers on the map. Not all the markers are right on a building, but they are close enough for me to see the areas from which attacks are coming.

Now on to the good stuff… Lire la suite…

Saving iptables rules for reboot

On a server, iptables rules don’t reload automatically at reboot. You need to reload the rules using ax executable shell scripture a dedicated utility that will load them at the same time as the program itself, i.e. with the kernel.

Depending of the version of Linux you use, you can select different methods:

sudo su
iptables-save > /etc/iptables.rules

In /etc/network/if-pre-up.d/iptables, put:

#!/bin/sh
iptables-restore < /etc/iptables.rules
exit 0

After, in /etc/network/if-post-down.d/iptables, put:

#!/bin/sh
iptables-save -c > /etc/iptables.rules
if [ -f /etc/iptables.rules ];
       then iptables-restore < /etc/iptables.rules
fi
exit 0

After, give permission to the scripts:

sudo chmod +x /etc/network/if-post-down.d/iptables sudo chmod +x /etc/network/if-pre-up.d/iptables

Another scenario is to is to install iptables-persistent:

sudo apt-get install iptables-persistent

After it’s installed, you can save/reload iptables rules anytime:

    sudo /etc/init.d/iptables-persistent save 
    sudo /etc/init.d/iptables-persistent reload

Or if you use Ubuntu server 16.04, things are simpler:

    sudo netfilter-persistent save
    sudo netfilter-persistent reload

Secure Apache Web Server – Practical Guide

1       Introduction

The Web Server is a crucial part of web-based applications. Apache Web Server is often placed at the edge of the network hence it becomes one of the most vulnerable services to attack. Having default configuration supply many sensitive information which may help hacker to prepare for an attack the web server.

The majority of web application attacks are through XSS, Info Leakage, Session Management and PHP Injection attacks which is due to weak programming code and failure to sanitize web application infrastructure. According to the security vendor Cenzic, 96% of tested applications have vulnerabilities. Below chart from Cenzic shows the vulnerability trend report of 2013.

This practical guide provides you the necessary skill set to secure Apache Web Server.  In this course, we will talk about how to Harden & Secure Apache Web Server on Unix platform. Following are tested on Apache 2.4.x and I don’t see any reason it won’t work with Apache 2.2.x.

1. This assumes you have installed Apache on UNIX platform. If not, you can go through Installation guide. You can also refer very free video about how to Install Apache, MySQL & PHP.
2. We will call Apache installation directory /opt/apache as $Web_Server throughout this course.
3. You are advised to take a backup of existing configuration file before any modification.

1.1  Audience

This is designed for Middleware Administrator, Application Support, System Analyst, or anyone working or eager to learn Hardening & Security guidelines. Fair knowledge of Apache Web Server & UNIX command is mandatory. This is seven page guide, click on Next to proceed. You may navigate through table of contents at right hand side.

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