How to hack WhatsApp in 2021 and how to protect it so that nobody can spy on your messages

WhatsApp is the world’s most popular messaging platform, with around 1.5 billion active users a month sending text messages, voice notes, multimedia content and PDF files from virtually everywhere. Although it was created by developers Brian Acton and Jan Koum, a couple of years ago WhatsApp was bought by Facebook, extending its dominance on digital platforms.

Due to its popularity, WhatsApp has become one of the favorite targets of threat actors, who have spent years trying to find the best method to compromise accounts on this platform.

Despite counting as end-to-end encryption, preventing actors outside the conversation from accessing messages, WhatsApp is affected by various security flaws that can be exploited by threat actors, as user-backed information is not protected by end-to-end encryption or other security variants.

On this occasion, the experts in mobile hacking of the International Institute of Cyber Security (IICS) will show you the most popular methods to hack WhatsApp accounts, in addition to listing some tips to prevent these attacks. As usual, we remind you that this article was prepared for informational purposes only, so IICS is not responsible for the misuse that may be given to the information contained herein.



This is a malicious practice in which hackers try to obtain sensitive information from a vulnerable user, including login credentials and browser cookies. In the case of WhatsApp, experts in mobile hacking mention that phishing focuses on stealing the QR code to log in to WhatsApp Web in order to steal the credentials of the web client.

Hackers use node.js and for the target website, deploying a cross-site scripting (XSS) attack in order to launch a new browser and connect with The hackers will then obtain the QR code data and send it to the client via the web socket connection. When the QR code is scanned, WhatsApp will authenticate the selenium-controlled browser and store some tokens in the local storage and document cookie.


Hackers can also use advanced tools to record each key pressed by the target user in order to extract their WhatsApp passwords. These tools, known as keyloggers, must be inadvertently installed on the target system so that the user has no knowledge that he is being spied on, as mention by the experts in mobile hacking.

When the target user opens WhatsApp on their phone, the keylogger starts collecting all the information entered into the device and stores it so that hackers can access the logs easily. There are several types of keyloggers available on the network, so threat actors have no major problems using these tools.

Mobile hacking

Mobile hacking tactics allow threat actors to give detailed tracking to the target user. Employing these methods, hackers can access detailed information such as call history, text messages, and list of installed apps, including WhatsApp.

According to experts in mobile hacking, this application is easily hackable using sophisticated cyberespionage tools . The good news is that these tools are very expensive and not available to any user.

SS7 attacks

Signaling System 7 (SS7) is a telecommunications standard responsible for defining how a telephone network exchanges information over a digital network. SS7 is in charge of number translation, billing, SMS message services, among other telecommunications services, mention experts in mobile hacking.

Threat actors can abuse known SS7 vulnerabilities in order to trick a telecommunications network into believing that the attacker’s phone has the same number as the victim’s. If the attack is successful, the hacker will be able to spy on the legitimate user by logging into a device other than the original; in other words, the hacker will be able to use the compromised account as if it were the affected user.

Session hijacking

This attack consists of taking control of the session on a valid device, gaining unauthorized access to sensitive information. According to mobile hacking specialists, this attack is more likely when using WhatsApp Web even though the service notifies users when a second active session is detected.

Despite the security measures on the platform, most users do not pay much attention to hints of malicious activity, so they could inadvertently confirm hackers’ access to their accounts on the messaging platform.

Social engineering

Not all hacking techniques involve the use of complex intrusion schemes and sophisticated security tools, as threat actors have multiple methods to get what they want without even using malicious code.

Social engineering is based on the extraction of confidential information through deception, saturating the user with messages, phone calls or emails in which they are offered fake products or services to gain the trust of victims and force the delivery of confidential information, in this case passwords and WhatsApp authentication codes.

WhatsApp Hack Tool

For some years now, various cybercriminal groups have been dedicated to the development of hacking tools to extract information from WhatsApp. One of the most famous examples is WhatsApp Hack Tool, a tool sold on the dark web, easy to use, with advanced features to compromise accounts on the messaging platform and that also works for both iOS and Android.

Experts in mobile hacking claim that this tool works thanks to the recreation of a security bug in the WhatsApp database. The hackers created a “worm” that goes unnoticed by almost any security solution, allowing the full compromise of the affected account.

DNS spoofing

In this attack, hackers must direct the target user to a legitimate-looking malicious website, divert web traffic, and steal login credentials. While this isn’t the stealthiest attack on this list, threat actors can go unnoticed for a long time.

Once a human language is entered into the computer, a DNS server finds the real IP address and then redirects the request from the user’s browser to the real machine based on the IP address. Ultimately, hackers employ this attack technique to hijack the real address of the WhatsApp website and redirect it to another IP address controlled by the attackers.

Using Firesheep

Firesheep is a tool capable of a packet sniffer to intercept unencrypted session cookies from websites such as Facebook and Twitter. According to experts in mobile hacking, this tool only works when the attacker and the victim are connected to the same network, since this condition facilitates the interception of cookies to improperly access the user’s WhatsApp account.


As we can see, threat actors have multiple resources at their disposal to compromise WhatsApp accounts, so users should keep their devices and online accounts secure enough to prevent most conventional hacking attempts.

Among the best security measures for WhatsApp are:

  • Avoid using unsupported versions of WhataApp
  • Make sure your messages are not copied to Google Drive or iCloud
  • Enable multi-factor authentication on your online accounts
  • Avoid connecting your devices to public WiFi hotspots as they are very insecure
  • Do not share personal information with anyone, especially by phone or email
  • Avoid installing mobile apps from unofficial platforms
  • Always log out of WhatsApp Web when you finish using the platform
  • Keep your WhatsApp app always up to date

To learn more about information security risks, malware variants, vulnerabilities and information technologies, feel free to access the International Institute of Cyber Security (IICS) websites.