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Showing posts from 2014

WhatsApp Hacking- Contacts Population: Part 12 of 12

In the previous 11 steps, we saw how easy it is to populate a series of contacts in gmail. now, if you sysnc this gmail with your device installed whatsApp, WhatsApp automatically searches for theese contacts in its database, and lists you with the contacts profile pictues and their contact number. You see how unsecured it is..?

How to Protect yourself?
Here is the Precautions you can take against Contacts Population for yourself and your loved ones:

1: check privacy settings in your whatsapp:

Under Settings -> Account -> Privacy:  set "Profile Photo" optionas "My contacts" 
This will prevent contacts population hackers getting your photos.

2: Do not respond to the messages from unknown numbers

3: Use the contacts Block option if you suspect sombody populated your contact and messaged you.

Thank you for reading this series of posts. I will be back with other interesting articles soon. :)

Whatsapp Hacking- Contacts Population: Part 11 of 12

In this step, we import the newly created contacts.csv to out gmail contacts, using the contacts import option.All the newly populated contacts will appear in the gmail contacts.

After importing the contacts it will look like this in gmail:

Whatsapp Hacking- Contacts Population: Part 10 of 12

In the WhatsApp hacking 10th step, we export the excel sheet we are working with now to google csv format by saving it.
We have to click on yes to keep the contacts in .csv format.

Now open the google.csv we just edited again in excel. It should look like this:

Whatsapp Hacking- Contacts Population: Part 9 of 12

In WhatsApp hacking part 9, we have to copy the whole first column by selecting it and paste it to the second and third columns. This is to fill the name and contact number fields of the addressbook we are generating.

Whatsapp Hacking- Contacts Population: Part 8 of 12

Whatsapp Hacking - Contacts Population method : Part 8

Now in part 8, we have to expand the full list of numbers we have to add to the contacts by selecting the two columns we entered in step 7 and dragging down. here in this example i dragged it upto 200 contacts, but you can actually drag up to 2500 contacts.

Whatsapp Hacking- Contacts Population: Part 7 of 12

Now the excel sheet looks like this:

Now , we have to hide the first line of the excel sheet, and enter the sequence if mobile numbers we have to add as part of the contacts population. First add the first two numbers to start with:

Whatsapp Hacking- Contacts Population: Part 6 of 12

After the last step (part 5), we got an excel sheet in this format with so many columns with different fields in the addressbook.

Now we have to hide whatever fields we do not reqire to edit .
for that, hide all the fields except "name", "given name", and "custom field1". Now it should look like this:

Go to part 6 for the next steps.

Whatsapp Hacking- Contacts Population: Part 5 of 12

In this step, convert the each entries into seperate colums using the "text to columns" feature in excel
It should look like this:

If you need help to do this : follow the following steps:
Click on " text to columns " button in data tab in ribbon and follow as the following pictures shows:

Whatsapp Hacking- Contacts Population: Part 4 of 12

Step 4: Open the google.csv file exported to your computer using excel sheet. Since my contacts are emptied, it looks like this:

See step 5 in Part 5

Whatsapp Hacking- Contacts Population: Part 2 of 12

As i explained in part 1, i am going to explain directly how a contact population is done in practical.

Step 1:
First , log into your gmail account, ( may be a test account to do this). and Go to contacts page.. ( direct link is

see next steps in Part 3

Whatsapp Hacking- Contacts Population: Part 3 of 12

Step 3: Export the existing contacts to google csv format:
see next steps in part 4

WhatsApp Hacking- Contacts Population: Part 1 of 12

Dear friends,
Did you ever get messages from unknown numbers ? Probably you are a victim of the Contacts Population vulnerability. Dont worry, I explained in the 12th post in this series how you can protect yourselves and your loved ones against this vulnerability effectively. You can find that article here
In this article, I am going to explain how this Contacts Population  technique works. This article is only for education purposes, and to alert my readers how serious it is before you or some of your loved ones become the victims of this.

What is Contacts Population Vulnerability? As the name indicates, this is a technique to generate a number of real contacts. These contacts can be used to send spam messages or to send messages to unknown numbers. At the time of writing this article, Many instant messaging apps lime Whats-app, line and Viber are vulnerable to Contacts population method.

How Contacts Population Works? As you know, Whats-app automatically finds the numbers stored i…

How to install FTP server in linux

Configuring vsftpdvsftpd is the package to install ftp server in linux. to install vsftpd:
using apk:   apk add vsftpdusing rpm: using apt ( ubuntu): sudo apt get install vsftpd   to configure ftp:
vi /etc/vsftpd/vsftpd.conf

any user defined in /etc/passwd will be able to login with their relevant passwords.
write_enable=YES  to emable  write access to the ftp server
anonymous_enable=YES allow anonymous FTP access

To restart FTP and load the new configuratrion: /etc/init.d/vsftpd restart
 Getting 500 OOPS child died Error? This error may appear if you are running vsftpd version 3.0.2. Add this following line to  /etc/vsftpd/vsftpd.conf to fix this issue: seccomp_sandbox=NO

How to Install Android in Windows 7

I am going to explain how an android virtual machine can be run inside a windows 7 OS. Runing androind in Windows gives many advantage that many apps which are freely available only in adroid can be used in windows systems.
Step 1: install Virtualbox in your computer
Presently, VirtualBox runs on Windows, Linux, Macintosh, and Solaris hosts and supports a large number of guest operating systems including but not limited to Windows (NT 4.0, 2000, XP, Server 2003, Vista, Windows 7, Windows 8), DOS/Windows 3.x, Linux (2.4, 2.6 and 3.x), Solaris and OpenSolaris, OS/2, and OpenBSD.
You can Download latest version of virtual box from:

Step 2: Download the Android Virtual Machine Image file. android 4.1.1 image can be downloaded from here:

Step 3:Import Virtual Machine
Now, you can import the VM into VirtualBox. Just double-click on the OVA file, or use “F…

How to temporarily stop Whatsapp , Viber Messaging in android

One of my friends told me that he want to stop Whatsapp and viber and other messaging apps temporarily on his android mobile phone.  Every one would like to keep their private messages private.   One practical way to do this is delete the confidential messages before giving the phone to someone else.   Even though you delete all the messages, the new messages will be delivered directly into the device if the internet is connected to phone. And it is not always possible to disconnect the internet access, as the other person may wanted to browse internet.  Here i am going to explain a simple way to do it.

 Droidwall APP-  Power of firewall to your mobileDroidwall is the android app for the famous iptables firewall in Linux operating systems.
Using Droidwall firewall, like any other firewall, you can define rules which apps can access internet and through which connection very easily with a simple front end GUI.
You can find the Droidwall app here in googplaystore:…

How to manage RAID in Linux

mdadm is a standard software tool to manage RAID in Linux.

to identify a faulty hard disk in a RAID, we can use the command

cat /proc/mdstat

if the raid array is good, we can see the string [UU] . If one of the Disk is failed or faulty, we can see [U_] or [_U]

to mark a disk in RAID as failed:

mdadm --manage /dev/md0 --fail /dev/sdb1

To remove a disk from RAID:

mdadm --manage /dev/md0 --remove /dev/sdb1

To remove the hard disk , we need to identify the failed hard disk physically.
Identifying using the serial number is easy and practical.

To identify the serial number of a hhard disk:

hdparm -I <device> | grep "Serial Number:"

To add a new hard disk to RAID:

a) copy the partition table from existing disk
sfdisk -d /dev/sda | sfdisk /dev/sdb

b) to list the partition table :
fdisk -l

c) add the nee hard disk to RAID:
mdadm --manage /dev/md0 --add /dev/sdb1

d) verify the status of the RAID
cat /proc/mdstat

How to Categorize blogger posts based on subject

Any blogger would like to post about different things in the same blog like me :)
Like a computer engineer may like to write about android programming and something about blogging techniques and something about linux tutorials and something about networking, some interesting photos, etc.

To do this, We can use a Feature called Labels in blogger.

The Labels Option is available in the right side column of the post-editor, like shown in the above picture.
Add Labels GadgetFrom the Blogger Dashboard go to the Layout tab

The layout screen will open.    On it. the Add a Gadget links show you all the places that you can currently add a gadget.

Choose one of these place.

Click the Add a gadget link at the top of the area you choose.
Choose Labels gadget from the list

How to hide Whatsapp photos and videos from Android Gallery

This is a very simple way to hide Whatsapp photos and videos from Android Gallery.

What you need:Any file Manager app. I am using ES File Explorer (

How to do:

Step 1: Enable "show hidden files option in File Explorer
                how to do this:

a)Click on Settings
b)select display settings c) check " show hidden files" option
Step 2: Copy the file named ".nomedia" from "Profile Pictures" folder Under "Whatsapp" folder
Step 3: Paste the ".nomedia" file into "Whatsapp" folder

You can also create an empty file with name ".nomedia" (note the file name begins with '.')
The gallery ignores any folders which contains a file named '.nomedia'