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Download Altaro Free VM Backup & Win a PlayStation 4 Pro, Xbox One X, 3-Year Amazon Prime and more!

Posted in Windows Server 2016

We have some exciting news for you today!

Altaro has launched a great contest in celebration of SysAdmin Day on 27th July 2018!

They will be giving away Amazon eGift Cards to the first 100 eligible entries and 1 Grand Prize to 1 lucky winner.

The Grand Prize winner will be able to choose any prize from the following: a PlayStation 4 Pro, Xbox One X, a 3-year membership of Amazon Prime, an Unlimited Plus Edition of Altaro VM Backup, and more!

All contest participants will even get FOREVER FREE backup for 2 VMs when they download Altaro VM Backup!

altaro 2018 syadmin day - Free Grand Prizes

Want to WIN?

Here’s what you need to do to:

  1. Download Altaro VM Backup from https://goo.gl/Zvedfs using a valid work email address
  2. Set up a virtual machine on Altaro VM Backup and take a screenshot. Only screenshots that show at least 1 VM added for backing up will be considered as eligible.
  3. Upload the screenshot and the Grand Prize choice at the link you will receive via email once you download Altaro VM Backup from the contest landing page.

Good luck!

Complete Guide to DHCP Snooping, How it Works, Concepts, DHCP Snooping Database, DHCP Option 82, Mitigating DHCP Starvation Attacks, DHCP Hijacking, Man-in-the-Middle Attacks & Rogue DHCP Servers

Posted in Cisco Switches - Catalyst Switch Configuration

This article covers popular Layer 2 & Layer 3 network attacks with a focus on DHCP Starvation Attacks, Man-in-the-Middle attacks, unintentional rogue DHCP servers and explains how security features like DHCP Snooping help protect networks from these attacks. We explain how DHCP Snooping works, cover DHCP Snooping terminology (trusted, untrusted ports/interfaces) and more. Finally we talk about the importance and purpose the DHCP Snooping Binding Database also used by Dynamic ARP Inspection to prevent ARP Poisoning and ARP Spoofing attacks.

Topics covered include:

DHCP Starvation Attack, Man-in-the-Middle Attack, DHCP Hijacking & Reconnaissance Attacks

DHCP Starvation attack is a common network attack that targets network DHCP servers. Its primary objective is to flood the organization’s DHCP server with DHCP REQUEST messages using spoofed source MAC addresses. The DHCP server will respond to all requests, not knowing this is a DHCP Starvation attack, and assign available IP addresses until its DHCP pool is depleted.

At this point the attacker has rendered the organization’s DHCP server useless and can now enable his own rogue DHCP server to serve network clients. DHCP Starvation is often accompanied by a Man-in-the-Middle attack as the rogue DHCP server distributes fake IP address parameters, including Gateway & DNS IP address, so that all client traffic passes through the attacker for inspection.

rogue dhcp server man in the middle attackTypical Man-in-the-Middle attack. Client data streams flow through the attacker

Using packet capture and protocol analysis tools the attacker is able to fully reconstruct any data stream captured and export files from it. In fact the process so simple it only requires a basic level of understanding of these type of network tools.

In other cases the Man-in-the-Middle attack can be used as a reconnaissance attack with the objective to obtain information about the network infrastructure, services but also identify hosts of high interest such as financial or database servers.

It should be by now evident how a simple attack can become a major security threat for any organization. The above attacks are examples on how easy hackers can infiltrate the network and get access to valuable information by simply connecting an unauthorized/untrusted device to an available network port effectively bypassing firewalls and other levels of security.

Rogue DHCP Servers – A Major Security Threat & Source of Network Disruptions

Rogue DHCP servers are a common problem within enterprise organizations and are not always directly related with an attack. Rogue DHCP Servers tend to appear out of nowhere thanks to users who connect consumer-grade network devices to the network infrastructure unaware that they have connected an unauthorized device with a rogue DHCP server enabled.

The Rogue DHCP server then begins assigning IP addresses to hosts within the network therefore causing network connectivity problems and in many cases – major service disruptions. In a best case scenario DHCP clients are served with an invalid IP address disconnecting them from the rest of the network. Worst case scenario would be the clients been assigned an IP address used by network infrastructure devices e.g the VLAN interface on the Core switch or a firewall interface, causing serious network disruptions and conflicts.

rouge dhcp server in action
A rogue DHCP server in action, taking control of DHCP services

While many organizations enforce security policies that do not allow 3rd party or unauthorized devices to be connected to their network, there are still incidents where users who do not understand (or care about) the security implications continue to connect these devices to the network infrastructure without consulting their IT Department.

Educating users and enforcing security policies can be extremely challenging which is why security mechanisms need to be in place to help mitigate these incidents and is where DHCP Snooping comes into the picture.

DHCP Snooping Support for Cisco Catalyst and Nexus Switches. Licensing & Features

Acunetix v12: More Comprehensive, More Accurate and now 2X Faster Web Vulnerability Scanner

Posted in Web Application Vulnerability Scanners

acunetix logo22nd May 2018: Acunetix, the pioneer in automated web application security software, has announced the release of version 12. This new version provides support for JavaScript ES7 to better analyse sites which rely heavily on JavaScript such as SPAs. This coupled with a new AcuSensor for Java web applications, sets Acunetix ahead of the curve in its ability to comprehensively and accurately scan all types of websites. With v12 also comes a brand new scanning engine, re-engineered and re-written from the ground up, making Acunetix the fastest scanning engine in the industry.

“Acunetix was always in the forefront when it came to accuracy and speed, however now with the re-engineered scanning engine and sensors that support the latest JavaScript and Java technologies, we are seeing websites scanned up to 2x faster without any compromise on accuracy.” announced Nicholas Sciberras, CTO.

A free trial version can be downloaded from: http://www.acunetix.com/vulnerability-scanner/download/

Support for latest JavaScript

acunetix v12 introAcunetix DeepScan and the Acunetix Login Sequence Recorder have been updated to support ECMAScript version 6 (ES6) and ECMAScript version 7 (ES7). This allows Acunetix to better analyse JavaScript-rich sites which make use of the latest JavaScript features. The modularity of the new Acunetix architecture also makes it much easier now for the technology to stay ahead of the industry curve.

AcuSensor for Java

Acunetix version 12 includes a new AcuSensor for Java web applications. This improves the coverage of the web site and the detection of web vulnerabilities, decreases false positives and provides more information on the vulnerabilities identified. While already supporting PHP and ASP .NET, the introduction of Java support in AcuSensor means that Acunetix coverage for interactive gray box scanning of web applications is now possibly the widest in the industry.

acunetix web vulnerability scanner v12 AcuSensor for Java

Speed and efficiency with Multi-Engine

Combining the fastest scanning engine with the ability to scan multiple sites at a time, in a multi-engine environment, allows users to scan thousands of sites in the least time possible. The Acunetix Multi-engine setup is suitable for Enterprise customers who need to scan more than 10 websites or web applications at the same time. This can be achieved by installing one Main Installation and multiple Scanning Engines, all managed from a central console.

Pause / Resume Feature

Acunetix Version 12 allows the user to pause a Scan and Resume the scan at a later stage. Acunetix will proceed with the scan from where it had left off. There is no need to save any scan state files or similiar - the information about the paused scan is automatically retained in Acunetix.

acunetix web vulnerability scanner paused scan

A free trial version can be downloaded from: http://www.acunetix.com/vulnerability-scanner/download/

SD-WAN is the Emerging, Evolving Solution for the Branch Office

Posted in SD-WAN

sd-wan the evolving solution for branch officesA lot has changed in how people work during the past twenty years. Co-working spaces, mobility, and the cloud now are common. Businesses are spread out and branch offices are empowered.

This new functionality is a good thing, of course. But, at the same time, it raises a big challenge: Multiprotocol Label Switching (MPLS), the way in which most branch offices network today, is a poor match for this new environment. It is an expensive and rigid one-size-fits-all approach to an environment that prizes fluidity and flexibility.

The answer is Software Defined-Wide Area Networking (SD-WAN). It matches the network to branch offices’ needs and provides a superior user experience. It also the potential to reduce costs.

Our Complete Guide to SD-WAN Technology article provides an in-depth coverage on SD-WAN Security, Management, Mobility, VPNs, Architecture and more.

SD-WAN is still a work in progress, no doubt, but the technology is positioned to be the next wave in branch office connectivity -- here's why.

Welcome to the New Branch

Enterprises generally configure WANs in a classic hub-and-spoke manner. Branches are the ends of the spokes and resources are in the hub, typically the headquarters or datacenters. Internet traffic is backhauled across the MPLS-based WAN to the hub for delivery through a secured, Internet access connection.  

That’s a solid, bulletproof approach. However, branch operations have changed radically since MPLS was introduced in the early 1990s. Back then, branch offices were comfortable with a T1 or two. Today's offices need 5x that amount. Back then, most applications and services terminated at MPLS-attached datacenters, not the Internet. Today, most traffic goes out to the Internet. Back then most work was done in offices. Today, work is done, well, everywhere.

MPLS Problems Hurt the New Branch

MPLS-based architectures are a poor fit for the new branch. Bandwidth is far more costly than Internet access (exact amounts will vary between regions and packages). Installation can take months, especially if the provider doesn’t have any available circuits; bandwidth upgrades weeks. This, needless to say, is too slow for today’s environment. International deployments only add to the problems.

The cost and inflexibility of MPLS leads many organizations to skimp on branch office bandwidth and, often, skip on redundancy. Instead, the sites instead are linked by non-redundant cable, DSL or wireless services and therefore are vulnerable to circuit failures and downtime. The use of separate networks makes creating a fully meshed architecture, where every office has a direct connection to every other office, far more difficult, impacting Active Directory and VoIP design. Those connected to MPLS face delays when more bandwidth is needed, such as for branch expansions and seasonal traffic spikes.  

The same antiquated approach extends to contracts. Branch offices often are temporary. One may start in somebody’s home. That worker may quickly be grouped with other workers at a larger branch across town. The three-year contracts offered by MPLS providers is simply inappropriate for such small- or transient-branch offices.

And none of this says anything about two shifts in enterprise networking -- the cloud and mobility. Backhauling Internet traffic adds too much latency, disrupting with the user experience. Often traffic is backhauled only to be sent back across the Internet to a site near the edge. This back and forth -- aptly called the “trombone effect” -- causes significant latency problems and consumes expensive MPLS bandwidth, particularly when the central portal and branch office are far from each other.

No Support for Mobile Users

Check Point Software and Cato Networks Co-Founder Shlomo Kramer Shares His Journey: From ‘Firewall-1’ Software to Today’s Firewall as a Service

Posted in SD-WAN

shlomo kramer cato networks founderBy: Shlomo Kramer, Check Point Software & Cato Networks Co-Founder

As one of the founders of Check Point Software and more recently Cato Networks, I’m often asked for my opinion on the future of IT in general, and security and networking in particular. Invariably the conversation will shift towards a new networking technology or the response to the latest security threat. In truth, I think the future of firewall lays in solving an issue we started to address in the past.

FireWall-1, the name of Check Point’s flagship firewall, is a curious name for a product. The product that’s become synonymous with firewalls wasn’t the first firewall. The category already existed when I invented the name and saved that first project file (A Yacc grammar file for the stateful inspection compiler, if you must know.) In fact, one of the first things Gil did when we started our market research for Check Point in 1992 was to subscribe to a newly formed firewall-mailing-list for, well, firewall administrators.

But FireWall-1 was the first firewall to make network security simple. It’s the stroke of simplicity that made FireWall-1. From software to appliances, firewall evolution has largely been catalyzed by simplicity. It’s this same dynamic that three years ago propelled Gur Shatz and me to start Cato Network and capitalize on the next firewall age, the shift to the cloud.

To better understand why simplicity is so instrumental, join me on a personal 25-year journey of the firewall. You’ll learn some little-known security trivia and develop a better picture of where the firewall, and your security infrastructure, is headed.

The Software Age and Simplicity Revolution

When we started developing FireWall-1, the existing firewalls were complicated beasts. Solutions, such as Raptor Firewall or Trusted Information Systems Firewall Toolkit (FWTK) relied on heavy professional services. Both came out of corporate America (If I remember correctly Raptor from DuPont and FWTK from Digital).

The products required on going attention. Using new internet applications could mean installing a new proxy server on the firewall. Upgrading an existing application could require simultaneously upgrading the existing proxy servers, or risk breaking the application. No surprise, the solutions were sold to large organizations willing to pay for the extensive customization and professional services required to implement and maintain them.

They say “necessity is the mother of invention” and that was certainly the case for Gil, Marius, and I. We were anything but corporate America. Extensive on-site support, custom implementations, professional services — the normative models wouldn’t work for us sitting in my grandmother’s apartment 10,000 miles away from the market, suffering the sweltering Israeli summer with no air conditioning and only $300,000 in the company bank account.

We needed a different strategy. What we needed was a solution that would be:

  • Simple to use without customer support,
  • Simple to deploy without professional services,
  • Simple to buy from a far, and, above all,
  • Simple enough for three capable developers to build before running out of budget (about 12 months).

To make the firewall simple to use, two elements were key:

  • A stateful and universal inspection machine that could handle any application given the right, light-weight configuration file. No longer was there a need to deploy and update custom proxy servers for each application. In the coming years, when Internet traffic patterns changed to include an ever growing number of applications, stateful inspection became critical.
  • An intuitive graphical user interface that any sys admin could understand and use almost immediately.

Actually, we didn’t get the UI right the first time around. After a few months of development, we ran a "focus group” with friends that luckily were PC developers. During those days, PC developers were much more advanced UI folk than us Sun Workstation guys. Our focus group hated the UI, which led us to start all over, and develop a PC-like interface that looked like this:

 checkpoint firewall 1 rule base editor

Caption: A screenshot of FireWall-1’s early interface.

 I still think it’s pretty great. By the way, you might notice a host called “Monk” in the rule base. It was one of the two Sun workstations we owned (actually borrowed as a favor from the Israeli distributor of Sun), and named Monk after Thelonious Monk, the American jazz pianist and composer. The other machine was named Dylan. And all of those cool Icons? They were drawn by Marius who doubled as our graphic artist. He worked on a PC.

To make the product simple to deploy, we made a special effort to compress the entire distribution into a single diskette with the install manual printed on the diskette’s label:

 checkpoint firewall-1 solaris fdd

Caption: An early FireWall-1 disk. Note the installation instructions on the label.

The last critical point was making the product simple to buy. In a world where the competition sold direct and made a considerable part of their revenues off of professional services, we decided to become a pure channel company and sell exclusively through partners.

We were very lucky to sign up early on with SunSoft, the software arm of the then leading computer manufacturer, Sun Microsystems, and become part of their popular Solstice suite. Sun's distribution know-how and capabilities were critical in the early days. In the pull market that followed, the fact that buying FW-1 through our partners was simple became critical.


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