WhatsApp open source intelligence investigation methods

WhatsApp is the world's largest instant messaging software. With more than 2 billion users, WhatsApp covers more than 180 countries and is among the most used instant messaging apps in 58 countries. Therefore, Whatsapp has information relevant to more than a quarter of the world's population.

As a messaging app rather than a social media platform, WhatsApp offers limited information gathering opportunities. However, there are a few techniques that can be used to gain insight into survey respondents through the platform.



Identify the phone number registered on WhatsApp

The most common way to check if a phone number has an associated WhatsApp account is to add it to your phone's contact list. WhatsApp uses the WhatsApp contact list and the native contact list to identify registered app users with users from other platforms.

But this method is not perfect. Because some mobile apps may have previously collected contact lists and sold them to data aggregators. Some cell phone lookup providers like https://sync.me/ and open source intelligence providers like PIPL may tag names saved in the contact list as phone numbers in their public records. Adding a contact to your phone may also inadvertently add it to your LinkedIn contacts list instead of WhatsApp.

In addition, it is possible to make the URL query the WhatsApp API to check if a phone number is registered for a WhatsApp account without adding it to your phone contacts.

If opened in a web browser, you can use the following URL, replacing "NUMBER" with the target phone number: https://api.whatsapp.com/send/?phone =NUMBER or https://wa.me/NUMBER Then go to the page.

Clicking on the "Continue To Chat" button will redirect you to a web page where you can select a hyperlink "use WhatsApp Web".

If the phone number is registered with WhatsApp, a blank chat window will open. If the phone number is not registered, you will receive a message saying " Phone number shared via url is invalid".

The process is similar if the check is done on the phone.

Entering the phone number in the URL, https://api.whatsapp.com/send/?phone = NUMBER or https://wa.me/NUMBER will direct you to a web page containing a button labeled "Continue To Chat". Opening this button will open a new chat window if the phone number is associated with an account.

If the number is not registered, a message will appear saying "The phone number isn't on WhatsApp".



Download WhatsApp profile picture

Profile pictures of WhatsApp users can be downloaded by using the WhatsApp web version.

After setting up WhatsApp Web Edition on your device first, you can find your previous chats in the left menu.

To find a phone number that has been added to the contact list, search for the contact name in the search field. You can right-click on an image in the left menu without opening a new chat window.

Alternatively, you can use the URL to determine if a phone number is registered with WhatsApp. if a phone number is registered with WhatsApp, a blank chat window will open, allowing you to extract their image.

Click on the profile photo in the Contact Information section to open a full-size version of the image.

Or, right-click on an image in the Contacts list or in the Contact section and select Open in new tab to look up the URL of the image.



WhatsApp search operators

WhatsApp content can be searched for using advanced search operators on search engines. However, results may be limited and depend on the chat link posted on the page.

· chat.whatsapp.com "topics"

Searching by WhatsApp chats and topics (e.g. chat.whatsapp.com "cricket") allows investigators to search for any public group chat that may be relevant to the topic of their investigation.



· Site:http://instagram.com

http://chat.whatsapp.com AND "name"

Searching on Instagram, investigators can search for topics or business names, such as on:

http://instagram.com

http://chat.whatsapp.com AND "Traders Club" to find if there are linked chats pointing to any WhatsApp.



· Site:http://4chan.org

http://chat.whatsapp.com AND "phrase"

Searching on 4Chan forums, investigators can search for a topic, such as on Site: http://4chan.org

http://chat.whatsapp.com "Origami", to determine if open groups are shared that may be related to the topic under investigation chat history.