Networking Tips Tricks

Adobe has released security updates to address multiple vulnerabilities in Flash Player. Exploitation of some of these vulnerabilities may allow a remote attacker to take control of an affected system. For securing your pc/laptop it must be updated to its latest version - 20.0.0.267 . In order to do this please follow the below instructions (Please note that in Chrome browser, the plugin is updated automatically): 1.       please enter the following link: Adobe Flash Playerdownload . 2.       Remove the V from the optional offers checkboxes 3.       Click on the "Install now" button 4.       Save the installation file. 5.       Open your download folder and locate the Adobe Flash Player installer file. Then double-click on the installer to complete the installation. 6.       Choose " Notify me to install updates "...

Hackers have discovered the first bug that could put Microsoft windows XP customers & users at serious threat, after Microsoft company stopped support for the aging operating system XP less than three weeks ago. On Saturday, Microsoft announced that Microsoft Internet Explorer (version 6 through 11) contains a Zero day vulnerability. This can allow arbitrary code execution. While using internet, users might  ‘Click‘ links/popup in a webpage or a Spam Email (attachment) – Once users click it , an attacker could take complete control of the system . Currently, Microsoft not yet released a patch to fix this breach – SO it is a RISK for all Internet Explorer users. 

file & directory protection is a essential of any OS and Linux OS is no exception for it! These authorizations allow you to choose exactly who can access your files & directory, providing an overall improved system security. There was one of the major flaws in the older Windows operating-system where, by standard, all users can see each other people's information (Windows 95, 98, Me). For overcoming it, editions of the Windows based computer system such as NT, 2000, XP and 2003 lot more security features added. They fully support file & directory permissions, just as Linux system has since the beginning. Together, we'll now assess a directory listing from our Lab Linux system hosting server, to help us understand the information provided. a simple 'ls' command will give you the file and directory listing within a given directory, including the option  '-l' will display number of new areas that we are going to discuss here:

What is a WEP Key? Wired Equivalent Privacy  ( WEP ) is a weak security algorithm for IEEE 802.11 wireless networks. Introduced as part of the original 802.11 standard ratified in September 1999, its intention was to provide data confidentiality comparable to that of a traditional wired network. WEP, recognizable by the key of 10 or 26 hexadecimal digits, is widely in use and is often the first security choice presented to users by router configuration tools. Although its name implies that it is as secure as a wired connection, WEP has been demonstrated to have numerous flaws and has been deprecated in favor of newer standards such as WPA2. In 2003 the Wi-Fi Alliance announced that WEP had been superseded by Wi-Fi Protected Access (WPA). In 2004, with the ratification of the full 802.11i standard (i.e. WPA2), the IEEE declared that both WEP-40 and WEP-104 "have been deprecated as they fail to meet the...

Packet crafting is a technique that allows network administrators or hackers to probe firewall rule-sets and find entry points into a targeted system or network. This is done by manually generating packets to test network devices and behaviour, instead of using existing network traffic. Testing may target the firewall, IDS, TCP/IP stack, router or any other component of the network. Packets are usually created by using a packet generator or packet analyzer which allows for specific options and flags to be set on the created packets. The act of packet crafting can be broken into four stages: Packet Assembly, Packet Editing, Packet Play and Packet Decoding. Tools exist for each of the stages - some tools are focussed only on one stage while others such as Ostinato try to encompass all stages .

Password cracking  is the process of recovering passwords from data that has been stored in or transmitted by a computer system. A common approach is to repeatedly try guesses for the password. The purpose of password cracking might be to help a user recover a forgotten password (though installing an entirely new password is less of a security risk, but involves system administration privileges), to gain unauthorized access to a system, or as a preventive measure by system administrators to check for easily crackable passwords. On a file-by-file basis, password cracking is utilized to gain access to digital evidence for which a judge has allowed access but the particular file's access is restricted.

In my last post I introduced the concept of using white listing in order to review firewall logs. I discussed how this process can both simplify as well as expedite the log review process, by automating much of the up front work. In this post we will look at some actual examples, as well as start creating a firewall log parsing script. The basics of grep In order to show you the process of white listing your firewall logs, I am going to use grep. Grep is a standard Linux/UNIX tool, with free versions  available for Windows  (grab both the Binaries as well as the Dependencies). Grep is certainly not the most efficient tool for the job, but it is by far the simplest to learn. If you are a Perl, PHP, AWK&SED, SQL, etc. guru, by all means stick with your tool of choice. Simply mimic the process I’ve defined here using your appropriate command set. Grep is a pattern-matching tool. It allows you to search one or more files looking for a specific pattern. When the pattern is fou...

One of the most difficult and time consuming parts of maintaining a perimeter is reviewing firewall logs. It’s not uncommon for an organization to generate 50, 100, 500 MB or more worth of firewall log entries on a daily basis. The task is so daunting in fact, that many administrators choose to ignore their logs. In this series I’ll show you how to expedite the firewall log review process so that you can complete it faster than that morning cup of coffee. Why firewall log review is important I once took part in a panel discussion where one of my fellow SANS instructors announced to the crowd “the perimeter is dead and just short of useless”. I remember thinking I was glad I was not one of his students. I occasionally take on new clients and find that 7/10 times I can identify at least one compromised system they did not know about. In every case it has been the client’s own firewall logs that pointed me to the infected system. In the old days firewall log review was all about ch...

What is a Digital Signature? An introduction to Digital Signatures Tom (Tom's public key) (Tom's private key) Tom has been given two keys. One of Tom's keys is called a Public Key, the other is called a Private Key. Tom's Co-workers:    Anyone can get Tom's Public Key, but Tom keeps his Private Key to himself Jerry Henry Jenny Tom's Public key is available to anyone who needs it, but he keeps his Private Key to himself. Keys are used to encrypt information. Encrypting information means "scrambling it up", so that only a person with the appropriate key can make it readable again. Either one of Tom's two keys can encrypt data, and the other key can decrypt that data. Jenny (shown below) can encrypt a message using Tom's Public Key. Tom uses his Private Key to decrypt the message. Any of Tom's coworkers might have access to the message Jenny encrypted, but without Tom's Private Ke...

Nessus was a popular free and open source vulnerability scanner until they closed the source code in 2005 and removed the free “registered feed” version in 2008. A limited “Home Feed” is still available, though it is only licensed for home network use. Some people avoid paying by violating the “Home Feed” license, or by avoiding feeds entirely and using just the plugins included with each release. But for most users, the cost has increased from free to $1200/year. Despite this, Nessus is still the best UNIX vulnerability scanner available and among the best to run on Windows. Nessus is constantly updated, with more than 20,000 plugins. Key features include remote and local (authenticated) security checks, a client/server architecture with a GTK graphical interface, and an embedded scripting language for writing your own plugins or understanding the existing ones.

The terminology, hacking, was initially used to refer to the process of finding solutions to rather technical issues or problems. These days, hacking is used to refer to the process whereby intruders maliciously attempt to compromise the security of corporate networks to destroy, interpret or steal confidential data; or to prevent an organization from operating. Different terminology is used to refer to criminal hacking: Cracking Cybercrime Cyberespionage Phreaking To access a network system, the intruder (hacker) performs a number of activities: Footprinting:  This is basically the initial step in hacking a corporate network. Here the intruder attempts to gain as much information on the targeted network by using sources which the public can access. The  aim of footprinting is to create a map of the network to determine what operating systems, applications and address ranges are being utilized, and to identify any accessible open ports. The  methods used to foot...

A  network attack  can be defined as any method, process or means used to maliciously attempt to compromise the security of the network. There are a number of reasons why an individual(s) would want to attack corporate networks. The individuals performing network attacks are commonly referred to as  network attackers or hackers or crackers. A few  different types of malicious activities performed by network attackers and hackers are summarized here: Illegally using user accounts and privileges. Stealing hardware. Stealing software. Running code to damage systems. Running code to damage and corrupt data. Modifying stored data. Stealing data. Using data for financial gain or for industrial espionage Performing actions that prevent legitimate authorized users from accessing network services and resources. Performing actions to deplete network resources and bandwidth. A few reasons  why network attackers attempt to attack corporate networks  are liste...