Dark Reading is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them.Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Vulnerabilities / Threats

8/8/2019
09:00 AM
Connect Directly
Twitter
LinkedIn
RSS
E-Mail
50%
50%

WhatsApp Messages Can Be Intercepted, Manipulated

Check Point security researchers demonstrate how a dangerous security weakness in the messaging application can be abused to spread fake news and carry out online scams.

BLACK HAT USA 2019 – Las Vegas – Researchers from Check Point Software Technologies are once again warning about what they describe as a dangerous security weakness in the WhatsApp messaging application that can be abused to spread fake news and carry out various online scams.

In a technical presentation here yesterday, Check Point researchers Roman Zaikin and Oded Vanunu explained how an attacker could exploit the issue to alter the text of someone else's reply, change the identity of a message sender, or trick a user into sharing something publicly in a group that they might not have intended to share.

The researchers first surfaced the same issues in August 2018 in a report that described how attackers could intercept and manipulate WhatsApp messages in private and group chat settings. In a blog and in comments at the time to Dark Reading, Vanunu identified the issue as having to do with WhatsApp's failure to validate certain message parameters before encrypting and sending messages to the intended recipient.

Since then, Facebook-owned WhatsApp has fixed the issue that allowed attackers to trick users in a group chat into thinking they were sharing something in private when, in fact, it was visible to everyone else, he said.

However, the other two issues remain unmitigated and continue to give attackers a way to abuse WhatsApp in dangerous ways, Vanunu said. From Check Point's perspective, the vulnerabilities present a major threat and need to be addressed urgently, he noted.

"WhatsApp is not just an application. It is an infrastructure of more than 1.5 billion users with more than 56 billion messages per day," Vanunu said.  

WhatsApp's massive footprint makes it a big target for criminals attempting to spread fake news and carry out other malicious activities, he said. In some countries, including India and Brazil, rumors spread via WhatsApp have even resulted in the deaths of innocent people, Vanunu said.  In many countries, WhatsApp is also used for business application, so it is important that the issue gets resolved, he added.

According to Vanunu and Zaikin, WhatsApp's end-to-end encryption is strong and not the problem. Rather, the issue lies in the communication that happens between an individual's WhatsApp mobile app and its Web version when a user logs in.

Vanunu and Zaikin reverse-engineered the communication and identified several message parameters being exchanged between WhatsApp's mobile version and Web version. Among them were parameters pertaining to the content of the message, and those that identified the message sender and the contact or the group to which the message was intended.

The researchers found they could intercept the communication and manipulate the data associated with each parameter before any of it was encrypted. For instance, an attacker could use the "quote" feature in WhatsApp that references a previous message to change the identity of the original sender or alter the original message entirely. WhatsApp does not validate the data and instead just accepts the altered content, encrypts it, and forwards it to the intended recipient.

WhatsApp did not respond to a request for comment. But in a statement responding to Check Point's original report last year, the company denied any security issue. It likened the issue to someone altering the contents of an email to put words into the mouth of the sender.

A lot of it also has to do with how WhatsApp works. WhatsApp has noted that when someone replies to a message, the WhatsApp client copies the text available within the app and creates a kind of graphical representation that helps people follow the conversation. The reason for providing a sort of "quick reply" option is to help identify the source within the user's chat log if one exists.

WhatsApp has stressed that with its end-to-encryption, it does not store any messages on its own servers and therefore has no single reference point of any messages that is off the device itself. As a result, the only way to validate any data in messages being sent would be to log all messages, which would undermine privacy protections. It would also make it impossible to deliver messages to groups when a single person is not connected to it and undermine the ability for users to quote a message prior to a new group member, WhatApp said.

Related Content:

Jai Vijayan is a seasoned technology reporter with over 20 years of experience in IT trade journalism. He was most recently a Senior Editor at Computerworld, where he covered information security and data privacy issues for the publication. Over the course of his 20-year ... View Full Bio

Comment  | 
Print  | 
More Insights
Comments
Newest First  |  Oldest First  |  Threaded View
Mobile Banking Malware Up 50% in First Half of 2019
Kelly Sheridan, Staff Editor, Dark Reading,  1/17/2020
Active Directory Needs an Update: Here's Why
Raz Rafaeli, CEO and Co-Founder at Secret Double Octopus,  1/16/2020
New Attack Campaigns Suggest Emotet Threat Is Far From Over
Jai Vijayan, Contributing Writer,  1/16/2020
Register for Dark Reading Newsletters
White Papers
Video
Cartoon Contest
Current Issue
The Year in Security: 2019
This Tech Digest provides a wrap up and overview of the year's top cybersecurity news stories. It was a year of new twists on old threats, with fears of another WannaCry-type worm and of a possible botnet army of Wi-Fi routers. But 2019 also underscored the risk of firmware and trusted security tools harboring dangerous holes that cybercriminals and nation-state hackers could readily abuse. Read more.
Flash Poll
How Enterprises are Attacking the Cybersecurity Problem
How Enterprises are Attacking the Cybersecurity Problem
Organizations have invested in a sweeping array of security technologies to address challenges associated with the growing number of cybersecurity attacks. However, the complexity involved in managing these technologies is emerging as a major problem. Read this report to find out what your peers biggest security challenges are and the technologies they are using to address them.
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2019-20391
PUBLISHED: 2020-01-22
An invalid memory access flaw is present in libyang before v1.0-r3 in the function resolve_feature_value() when an if-feature statement is used inside a bit. Applications that use libyang to parse untrusted input yang files may crash.
CVE-2019-20392
PUBLISHED: 2020-01-22
An invalid memory access flaw is present in libyang before v1.0-r1 in the function resolve_feature_value() when an if-feature statement is used inside a list key node, and the feature used is not defined. Applications that use libyang to parse untrusted input yang files may crash.
CVE-2019-20393
PUBLISHED: 2020-01-22
A double-free is present in libyang before v1.0-r1 in the function yyparse() when an empty description is used. Applications that use libyang to parse untrusted input yang files may be vulnerable to this flaw, which would cause a crash or potentially code execution.
CVE-2019-20394
PUBLISHED: 2020-01-22
A double-free is present in libyang before v1.0-r3 in the function yyparse() when a type statement in used in a notification statement. Applications that use libyang to parse untrusted input yang files may be vulnerable to this flaw, which would cause a crash or potentially code execution.
CVE-2019-20395
PUBLISHED: 2020-01-22
A stack consumption issue is present in libyang before v1.0-r1 due to the self-referential union type containing leafrefs. Applications that use libyang to parse untrusted input yang files may crash.