Zal.:.

Zal Walt

Introduction

Whenever security professionals recommend the 5 most important IT security practices to average users, one of the items is usually something like: "Avoid using open Wifi" or "Always use VPN while using open WiFi" or "Avoid sensitive websites (e.g. online banking) while using open WiFI", etc.

What I think about this? It is bullshit. But let's not jump to the conclusions. Let's analyze all risks and factors here.

During the following analysis, I made two assumptions. The first one is that we are comparing public WiFi hotspots with no encryption at all (referred to as Open), and we compare this to public WiFi hotspots with WPA2-PSK (and just hope WEP died years before). The other assumption is there are people who are security-aware, and those who just don't care. They just want to browse the web, access Facebook, write e-mails, etc.

The risks

Let's discuss the different threats people face using public hotspots, compared to home/work internet usage:

1. Where the website session data is not protected with SSL/TLS (and the cookie is not protected with secure flag), attackers on the same hotspot can obtain the session data and use it in session/login credentials stealing. Typical protocols affected:

HTTP sites
HTTPS sites but unsecured cookie
FTP without encryption
IMAP/SMTP/POP3 without SSL/TLS or STARTTLS

2. Attackers can inject extra data into the HTTP traffic, which can be used for exploits, or social engineer attacks (e.g. update Flash player with our malware) – see the Dark Hotel campaign

3. Attackers can use tools like SSLStrip to keep the user's traffic on clear text HTTP and steal password/session data/personal information

4. Attackers can monitor and track user activity

5. Attackers can directly attack the user's machine (e.g. SMB service)

WPA2-PSK security

So, why is a public WPA2-PSK WiFi safer than an open WiFi? Spoiler alert: it is not!

In a generic public WPA2-PSK scenario, all users share the same password. And guess what, the whole traffic can be decrypted with the following information: SSID + shared password + information from the 4-way handshake. https://wiki.wireshark.org/HowToDecrypt802.11

If you want to see it in action, here is a nice tutorial for you

http://www.lovemytool.com/blog/2010/05/wireshark-and-tshark-decrypt-sample-capture-file-by-joke-snelders.html

Decrypted WPA2-PSK traffic

Any user having access to the same WPA2-PSK network knows this information. So they can instantly decrypt your traffic. Or the attackers can just set up an access point with the same SSID, same password, and stronger signal. And now, the attacker can instantly launch active man-in-the-middle attacks. It is a common belief (even among ITSEC experts) that WPA2-PSK is not vulnerable to this attack. I am not sure why this vulnerability was left in the protocol, if you have the answer, let me know. Edit (2015-08-03): I think the key message here is that without server authentication (e.g. via PKI), it is not possible to solve this.

Let me link here one of my previous posts here with a great skiddie tool:

http://jumpespjump.blogspot.nl/2014/04/dsploit.html

To sum up, attackers on a WPA2-PSK network can:

Decrypt all HTTP/FTP/IMAP/SMTP/POP3 passwords or other sensitive information
Can launch active attacks like SSLStrip, or modify HTTP traffic to include exploit/social engineer attacks
Can monitor/track user activity

The only difference between open and WPA2-PSK networks is that an open network can be hacked with an attacker of the skill level of 1 from 10, while the WPA2-PSK network needs and an attacker with a skill level of 1.5. That is the difference.

The real solutions

1. Website owners, service providers should deploy proper (trusted) SSL/TLS infrastructure, protect session cookies, etc. Whenever a user (or security professional) notices a problem with the quality of the service (e.g. missing SSL/TLS), the service provider has to be notified. If no change is made, it is recommended to drop the service provider and choose a more secure one. Users have to use HTTPS Everywhere plugin.

2. Protect the device against exploits by patching the software on it, use a secure browser (Chrome, IE11 + enhanced protection), disable unnecessary plugins (Java, Flash, Silverlight), or at least use it via click-to-play. Also, the use of exploit mitigations tools (EMET, HitmanPro Alert, Malwarebytes AntiExploit) and a good internet security suite is a good idea.

3. Website owners have to deploy HSTS, and optionally include their site in an HSTS preload list

4. Don't click blindly on fake downloads (like fake Flash Player updates)

5. The benefits of a VPN is usually overestimated. A VPN provider is just another provider, like the hotspot provider, or the ISP. They can do the same malicious stuff (traffic injecting, traffic monitoring, user tracking). Especially when people use free VPNs. And "Average Joe" will choose a free VPN. Also, VPN connections tend to be disconnected, and almost none of the VPN providers provide fail secure VPNs. Also, for the price of a good VPN service you can buy a good data plan and use 4G/3G instead of low-quality public hotspots. But besides this, on mobile OSes (Android, iOS, etc.) I strongly recommend the use of VPN, because it is not practically feasible to know for users which app is using SSL/TLS and which is not.

6. Use a location-aware firewall, and whenever the network is not trusted, set it to a Public.

7. In a small-business/home environment, buy a WiFi router with guest WiFi access possibility, where the different passwords can be set to guest networks than used for the other.

Asking the question "Are you using open WiFi?", or "Do you do online banking on open WiFi?" are the wrong questions. The good questions are:

Do you trust the operator(s) of the network you are using?
Are the clients separated?
If clients are not separated, is it possible that there are people with malicious intent on the network?
Are you security-aware, and are you following the rules previously mentioned? If you do follow these rules, those will protect you on whatever network you are.

And call me an idiot, but I do online banking, e-shopping, and all the other sensitive stuff while I'm using open WiFi. And whenever I order pizza from an HTTP website, attackers can learn my address. Which is already in the phone book, on Facebook, and in every photo metadata I took with my smartphone about my cat and uploaded to the Internet (http://iknowwhereyourcatlives.com/).

Most articles and research publications are full of FUD about what people can learn from others. Maybe they are just outdated, maybe they are not. But it is totally safe to use Gmail on an open WiFi, no one will be able to read my e-mails.

PS: I know "Average Joe" won't find my blog post, won't start to read it, won't understand half I wrote. But even if they do, they won't patch their browser plugins, pay for a VPN, or check the session cookie. So they are doomed to fail. That's life. Deal with it.

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Zal Walt

DEFINATION OF HACKING

Hacking is an attempt to exploit a computer system vulnerabilities or a private network inside a computer to gain unauthorized acess.
Hacking is identifying and exploiting weakness in computer system and/ or computer networks for finding the vulnerability and loopholes.

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Zal Walt

Are you tired of reading endless news stories about ethical hacking and not really knowing what that means? Let's change that!

This Post is for the people that:

Have No Experience With Cybersecurity (Ethical Hacking)
Have Limited Experience.
Those That Just Can't Get A Break

OK, let's dive into the post and suggest some ways that you can get ahead in Cybersecurity.

I receive many messages on how to become a hacker. "I'm a beginner in hacking, how should I start?" or "I want to be able to hack my friend's Facebook account" are some of the more frequent queries. Hacking is a skill. And you must remember that if you want to learn hacking solely for the fun of hacking into your friend's Facebook account or email, things will not work out for you. You should decide to learn hacking because of your fascination for technology and your desire to be an expert in computer systems. Its time to change the color of your hat 😀

I've had my good share of Hats. Black, white or sometimes a blackish shade of grey. The darker it gets, the more fun you have.

If you have no experience don't worry. We ALL had to start somewhere, and we ALL needed help to get where we are today. No one is an island and no one is born with all the necessary skills. Period.OK, so you have zero experience and limited skills…my advice in this instance is that you teach yourself some absolute fundamentals.

Let's get this party started.

What is hacking?

Hacking is identifying weakness and vulnerabilities of some system and gaining access with it.

Hacker gets unauthorized access by targeting system while ethical hacker have an official permission in a lawful and legitimate manner to assess the security posture of a target system(s)

There's some types of hackers, a bit of "terminology".
White hat — ethical hacker.
Black hat — classical hacker, get unauthorized access.
Grey hat — person who gets unauthorized access but reveals the weaknesses to the company.
Script kiddie — person with no technical skills just used pre-made tools.
Hacktivist — person who hacks for some idea and leaves some messages. For example strike against copyright.

Skills required to become ethical hacker.

Curosity anf exploration
Operating System
Fundamentals of Networking

*Note this sites

Welcome back to the Linux Command Line Hackery series, this is Part-V of the series. Today we are going to learn how to monitor and control processes on our Linux box, so wrap your sleeves up and let's get started.

Command: ps
Syntax: ps [options]
Description: ps displays information about the currently running processes. Some of the common flags of ps are described briefly below
Flags:
-A or -e -> select all processes
-a -> select all processes except both session leaders and processes not associated with a terminal.
T -> select all processes associated with current terminal
-u <username or id> -> select all processes of a given user or userlist

Open up a terminal and type ps:

ps

what you'll see is a list of processes currently running in your terminal. One important thing to notice in the output is what's called as PID which stands for process ID. It is the number that uniquely identifies a process. Just keep that PID concept in mind we'll use it soon.

OK I know that's not really what you want to see rather you want to see all the processes that are currently running on your box. Don't worry we have flags to rescue, in order to see all the processes you can use the -e flag like this:

ps -e

Boom! you get a long list of processes currently running on your machine (don't stare at me like that, you asked and I gave you that). If you want to see processes of a particular user you can type the following command in your terminal:

ps -u bob

here "bob" is a username. This command will list all processes of the user with effective user name of bob.

You can do a full-format listing of the processes using the -f flag like this:

ps -fu bob

But the output of the ps command is a snapshot not really a live preview of what is going on in your box. I know your next question is going to be something like this, Isn't there a command in Linux that gives me a live updating information of the processes? Yes, there is a command called top that we'll learn about next.

Command: top
Syntax: top [options]
Description: top gives a dynamic real-time view of a running system. That is, it gives the up-to-date information about all the processes running on your Linux box (sounds fun!). Besides giving information about current processes and threads top also provides a brief system summary.

To start top just type this command:

top

and you'll get a nice and cute looking ugly display :). Well what the heck is going on here you might ask, right? What you get is information about what is going on with your computer. To see what more can you do with top just type <h> within the program window and you'll be given list of options that you can play with.

OK looking at what processes are going on in your box is cool but what if you want to terminate (or close) a process, is there a command line utility for that? Yes, there is and that's what we are going to look at next.

Command: kill
Syntax: kill [options] <pid> [...]
Description: kill is used to send a signal to process which by default is a TERM signal meaning kill by default sends a signal of termination to process (Cruel guy). To list the available signals we can use the -l or -L flag of the kill command.

To simply terminate a process we provide kill command a PID (process ID) and it will send the TERM signal to the process. So to kill a process first we'll list the running processes and then we'll keep the PID of the process in mind that we want to terminate. After that we'll issue the kill command with the PID that we just found.

ps -ax
kill 1153

the above command will send a TERM signal to the process whose PID is 1153, as simple as that.

We can also use our already learned skills to refine the output of ps command. Say we have a xterm terminal running on our box and we want to terminate it. By using ps command all alone we'll get a long listing of all processes running on our box. But we can limit the output of ps command to just those processes that we're interested in by piping ps command with the grep command like this:

ps -ax | grep xterm

wow! that's amazing, we're able to pull out only those results from the ps command that contained xterm in them. Isn't that a cool trick? But what is that vertical bar ( | ) doing in the middle, you may be thinking, right? Remember we learned about the input and output re-directors previously, the vertical bar (pipe in geeky terms) is another re-director whose task is to redirect the output of one command as input to another command. Here the pipe redirects the output of ps -ax command as input to grep command and of-course from the previous article you know that grep is used to search for a PATTERN in the given input. That means the above command searches for the xterm word in the output of ps -ax command and then displays just those lines of ps -ax command which contain xterm. Now get that PID and kill that process.

That's it for today, try these commands up on your own box and remember practice is gonna make you master the Linux command line. :)

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Zal.:.

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Introduction

The risks

WPA2-PSK security

The real solutions

Continue reading

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DEFINATION OF HACKING

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How To Start | How To Become An Ethical Hacker

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