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.

Mobile

Flaws in Telegram & WhatsApp on Android Put Data at Risk

App settings combined with Android behavior can put data integrity at risk for WhatsApp and Telegram users.

WhatsApp and Telegram are personal messaging apps that have, between them, more than 1.7 billion users around the world. They are frequently used by political activists, healthcare providers, and businesses around the world because of the security of their "always encrypted" communications. But recent research shows that there are security vulnerabilities that could open the services to manipulation and data theft for users on Android devices.

In a blog post today, Symantec researchers Yair Amit and Alon Gat discussed a media file jacking flaw in the way that the Android apps store files that the user receives. The researchers note that the flaw isn't in the app code, but in the app logic, specifically where the apps will store files that they receive.

"We found the vulnerability in the way on Android that WhatsApp (by default) and Telegram (in a certain setting) can store attachments like photos and audio messages before the user is able to open the original file," says Domingo Guerra, senior director of modern OS security at Symantec.

The trouble is that Android can store files in two locations — internal and external storage. Data in internal storage can only be accessed by the app that stored it. Data in external storage is defined as world readable and writeable — any app or user can read and modify the data.

WhatsApp stores received media files in external storage by default. Telegram uses external storage for its "Save to Gallery" feature. In both cases, the files are stored to publicly accessible directories.

According to Guerra, there are several kinds of damage that could result from the ability to intercept and manipulate files on an Android device — damage beyond the simple ability to see what sort of files are being sent back and forth between users.

In the blog post on the vulnerability, the researchers point out image manipulation, in which faces are changed or individuals inserted into images; audio manipulation, in which a "deepfake" technology makes it seem an individual is saying something they never actually said; invoice manipulation, in which the amount and payment details in a legitimate invoice are changed to send money into the attacker's account; and "fake news," in which the material sent out by a legitimate news organization is changed to become inaccurate, as possible harm from media file jacking.

To add to the vulnerability's seriousness, "You don't have to attack Telegram or WhatsApp for this to happen," says Guerra. "A device that already has malware that's monitoring for external storage could be vulnerable to replaced documents."

The apps' global footprints mean that the potential impact of these vulnerabilities. For example, Otavio Freire, CTO and president of SafeGuard Cyber, says, "In South America two years ago, doctors didn't use WhatsApp to communicate at all. Now, the adoption is 90% of Brazilian doctors who use WhatsApp for daily business."

And Freire says that more companies will be — and should be — using WhatsApp, Telegram, and other messaging apps going forward. "Companies that come to WhatsApp have come to it because it has significantly impacted their business processes," he says. "They do better marketing. They do better sales. They do better customer service. That's where the customers are, so if you ignore it, you're not where your customers are."

As for protection against the vulnerabilities, both Guerra and Freire say that some steps will be up the individual device owners — like setting WhatsApp to store files in internal storage and not using the "Gallery" function of Telegraph.

In addition, Freire points to the importance of saving archival copies of any corporate information transmitted by either app (or other messaging apps). In an era that sees the possibility of "deepfakes," they are necessary insurance against unwanted information going out to employees or customers.

Related content:

 

Black Hat USA returns to Las Vegas with hands-on technical Trainings, cutting-edge Briefings, Arsenal open-source tool demonstrations, top-tier security solutions, and service providers in the Business Hall. Click for information on the conference and to register.

Curtis Franklin Jr. is Senior Editor at Dark Reading. In this role he focuses on product and technology coverage for the publication. In addition he works on audio and video programming for Dark Reading and contributes to activities at Interop ITX, Black Hat, INsecurity, and ... View Full Bio
 

Recommended Reading:

Comment  | 
Print  | 
More Insights
Comments
Newest First  |  Oldest First  |  Threaded View
fwbrothers
50%
50%
fwbrothers,
User Rank: Apprentice
12/29/2019 | 12:02:45 AM
Re: Netgear Router issues
This is a great example of the constantly shifting security landscape that evolves with every new technology that is popularly adopted. Leave it to the folks that strive to generate revenue from gray or black hat practices and will continuously innovate new strategies to bend or break the rules that compromise security protocols in well established niches. A simple google search would provide numerous examples of the newest schemes being hatched
tonny123
50%
50%
tonny123,
User Rank: Apprentice
7/16/2019 | 2:00:20 AM
Netgear Router issues
very nice
Overcoming the Challenge of Shorter Certificate Lifespans
Mike Cooper, Founder & CEO of Revocent,  10/15/2020
7 Tips for Choosing Security Metrics That Matter
Ericka Chickowski, Contributing Writer,  10/19/2020
Register for Dark Reading Newsletters
White Papers
Video
Cartoon
Current Issue
Special Report: Computing's New Normal
This special report examines how IT security organizations have adapted to the "new normal" of computing and what the long-term effects will be. Read it and get a unique set of perspectives on issues ranging from new threats & vulnerabilities as a result of remote working to how enterprise security strategy will be affected long term.
Flash Poll
How IT Security Organizations are Attacking the Cybersecurity Problem
How IT Security Organizations are Attacking the Cybersecurity Problem
The COVID-19 pandemic turned the world -- and enterprise computing -- on end. Here's a look at how cybersecurity teams are retrenching their defense strategies, rebuilding their teams, and selecting new technologies to stop the oncoming rise of online attacks.
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2020-27621
PUBLISHED: 2020-10-22
The FileImporter extension in MediaWiki through 1.35.0 was not properly attributing various user actions to a specific user's IP address. Instead, for various actions, it would report the IP address of an internal Wikimedia Foundation server by omitting X-Forwarded-For data. This resulted in an inab...
CVE-2020-27620
PUBLISHED: 2020-10-22
The Cosmos Skin for MediaWiki through 1.35.0 has stored XSS because MediaWiki messages were not being properly escaped. This is related to wfMessage and Html::rawElement, as demonstrated by CosmosSocialProfile::getUserGroups.
CVE-2020-27619
PUBLISHED: 2020-10-22
In Python 3 through 3.9.0, the Lib/test/multibytecodec_support.py CJK codec tests call eval() on content retrieved via HTTP.
CVE-2020-17454
PUBLISHED: 2020-10-21
WSO2 API Manager 3.1.0 and earlier has reflected XSS on the "publisher" component's admin interface. More precisely, it is possible to inject an XSS payload into the owner POST parameter, which does not filter user inputs. By putting an XSS payload in place of a valid Owner Name, a modal b...
CVE-2020-24421
PUBLISHED: 2020-10-21
Adobe InDesign version 15.1.2 (and earlier) is affected by a memory corruption vulnerability due to insecure handling of a malicious .indd file, potentially resulting in arbitrary code execution in the context of the current user. User interaction is required to exploit this vulnerability.