Check Point security recently discovered a vulnerability in the WhatsApp Web application that allows hackers to take control of a users computer by sending them a file that looks like a vCard.
Check Point security researchers have recently discovered various vulnerabilities in the WhatsApp Web application. Hackers would exploit a user’s computer by sending them a vCard, but the vCard is actually an executable file and opens up a PC to malware and phishing attacks.
WhatsApp Web – a web-based extension of the WhatsApp application on a phone mirrors all messages sent and received, and fully synchronizes your phone and your desktop computer so that users can see all messages on both devices.
WhatsApp Web is available for most WhatsApp supported platforms, including Android, iPhone (iOS), Windows Phone 8.x, BlackBerry, BB10 and Nokia smartphones. In September 2015, WhatsApp announced they had reached 900 million active users a month. At least 200M are estimated to use the WhatsApp Web interface, considering publicly available web traffic statistics.
Check Point security researcher Kasif Dekel recently discovered significant vulnerabilities which exploit the WhatsApp Web logic and allow attackers to trick victims into executing arbitrary code on their machines in a new and sophisticated way. All an attacker needed to do to exploit the vulnerability was to send a user a seemingly innocent vCard containing malicious code. Once opened, the alleged contact is revealed to be an executable file, further compromising computers by distributing bots, ransomware, RATs, and other malwares.
To target an individual, all an attacker needs is the phone number associated with the account.
WhatsApp verified and acknowledged the security issue and have deployed the fix in web clients world-wide. To make sure you are protected, update your WhatsApp Web right now.
Check Point shared its discovery to WhatsApp on August 21, 2015. On August 27, WhatsApp rolled out the initial fix (in all versions greater than 0.1.4481) and blocked that particular feature.
WhatsApp Web allows users to view any type of media or attachment that can be sent or viewed by the mobile platform/application. This includes images, videos, audio files, locations and contact cards.
The vulnerability lies in improper filtering of contact cards, sent utilising the popular ‘vCard’ format.
This is a screenshot for a possible contact vCard sent by a malicious user:
As you can see, this message (contact card) appears legitimate, like any other contact card; most users would click it immediately without giving it a second thought.
The implication of this innocent action is downloading a file which can run arbitrary code on the victim’s machine:
An Initial Hole
During Kasif’s research, he found that by manually intercepting and crafting XMPP requests to the WhatsApp servers, it was possible to control the file extension of the contact card file.
He first changed the file extension to .BAT, which indicates a Windows batch (executable script) file:
This means, once the victim clicks the downloaded file (which he assumes is a contact card), the code inside the batch file runs on his computer.
Let’s see what’s inside the downloaded file (i.e. the batch file):
This is a standard vCard format. To run malicious code, Kasif found out an attacker could simply inject a command to the name attribute of the vCard file, separated by the ‘&’ character. When executed, Windows will attempt to run all lines in the files, including our controlled injection line.
Further research showed that no XMPP interception of crafting is needed for this attack, since any user can create such a contact with an injected payload on their phones, no hacking tools necessary:
Once such a contact is created, all an attacker has to do is share it via the normal WhatsApp client.
But can we take it to the next level? Could we possibly discover a way to share malicious PE (.exe) files through WhatsApp’s default sharing features (no external links)?
To answer that, we have to examine WhatsApp’s communication protocols; WhatsApp uses a customised version of the open standard Extensible Messaging and Presence Protocol (XMPP).
This is how vCard messages appear over-the-wire (with some reconstruction) when sent using WhatsApp’s protocol:
NUMBER/GROUPID: the victim’s number or group ID
· ID: the message ID
· TIMESTAMP: the timestamp of the sender device
· FILENAME: the VCARD file name, <something>.exe
· FILEDATA: the raw data of the file
We were surprised to find that WhatsApp fails to perform any validation on the vCard format or the contents of the file, and indeed when we crafted an exe file into this request, the WhatsApp web client happily let us download the PE file in all its glory:
But wait, there’s more! Clever attackers can exploit this in more devious scenarios, using the displayed icon to enrich the scam:
This simple trick opened up a vast world of opportunity for cybercriminals and scammers, in effect allowing easy “WhatsApp Phishing”. Massive exploitation of this vulnerability could have affected millions of users, failing to realise the malicious nature of the attachment.
· August 21, 2015 – Vulnerability disclosed to the WhatsApp security team.
· August 23, 2015 – First response received.
· August 27, 2015 – WhatsApp rolls out fixed web clients (v0.1.4481)
· September 8, 2015 – Public disclosure
“Thankfully, WhatsApp responded quickly and responsibly to deploy an initial mitigation against exploitation of this issue in all web clients, pending an update of the WhatsApp client” said Oded Vanunu, Security Research Group Manager at Check Point. We applaud WhatsApp for such proper responses, and wish more vendors would handle security issues in this professional manner. Software vendors and service providers should be secured and act in accordance with security best practices.
Check Point continues to be on the lookout for vulnerabilities in common software and Internet platforms, disclosing issues as they are discovered, protecting consumers and customers against tomorrow’s threats.”
SA startups in Visa final
Leading fintech companies from the Sub-Sahara Africa technology startup community have made it to the finals of Visa’s Everywhere Initiative.
Among the 12 chosen, from the 238 total entries, South African startups Howler and FinChatBot will compete against innovators from across Sub Sahara Africa for a chance to secure funding of up to US$50,000 to develop their ideas when the initiative concludes in Johannesburg on July 24.
Fintechs in Africa are making incredible strides; not only to bring more convenience to consumers, but also to enable people who would not otherwise have access to financial services or even a way to connect to the formal banking system. Venture funding for African startups jumped by 51% to $195 million in 2017 and fintech in Africa is expected to grow exponentially in the next few years as it continues to disrupt the traditional financial sector. With a clear goal of reducing reliance on cash, building digital payment based economies and increasing financial inclusion, Visa is committed to fostering an entrepreneurial spirit and driving innovation in its payments landscape.
The Sub Saharan Africa edition of the Visa’s Everywhere Initiative challenged local fintech startup to deliver solutions based around three real life business challenges:
- How can startups leverage Visa Developer APIs to either: Enable smaller merchants to accept payments in-store digitally OR Provide a safe and secure solution for online merchants to drive eCommerce and reduce cash on delivery?
- How can startups use Visa’s APIs to leverage mass reach and social media partner platforms like Facebook to help businesses operating in fast-paced consumer centric environments improve cash flow and receive payments?
- How can startups leverage technology to provide services that are functional for illiterate customers to provide them with secure transaction experiences that build and enhance their confidence in the banking system?.
Entrants were asked to submit ideas to leverage Visa’s network and technologies to resolve against at least one of the challenges. One winner per brief will be selected, with each receiving funding of US$25,000. Winners will be invited to a working meeting with Visa and may be presented with the opportunity to create a prototype. Visa will then select one overall winner to receive an additional US$25,000.
Geraldine Mitchley, Senior Director – Digital Solutions, Sub-Sahara Africa, Visa, said: “We are delighted with the response to our Visa’s Everywhere Initiative and the quality of submissions we received is an indication of the region’s rich talent pool and innovative spirit.”
“Launching this innovation program in the region has been an exciting time for the Visa SSA team, and the takeup reflects Africa’s enthusiasm to develop and pioneer solutions to the continent’s challenge – particularly in the payments technology space. I would like to congratulate the finalists and wish them luck as they enter the final stretch. When they come together for the final, they will not only have the chance to turn their ideas into reality, but also potentially help shape the future of payments in the region.”
Howler which enables cashless transactions and end-to-end ticket handling for consumers and event organisers is competing in the first challenge and FinChatBot, which aims to automate part of customer services for financial service providers through AI-powered conversations is competing in the third challenge.
The SSA edition of the Visa’s Everywhere Initiative will wrap up on July 24 in Johannesburg, with each finalist having an opportunity to pitch their ideas to a panel of expert judges from Visa and the payments industry.
Win a Poster Heater with Gadget and Takealot.com
This winter Gadget and Takealot.com are giving away three Poster Heaters, which look like posters but become heaters when you plug them in.
Three Gadget readers will each win a unit, valued at R550 each. To enter, follow @GadgetZA and @Takealot on Twitter and tell us on the @GadgetZA account how many Watts the heater consumes.
What’s the big deal about these heaters? Many of us are struggling to keep the balance between soaring electricity costs and the need to keep warm this winter.
However, the recently launched Poster Heater by EasyHeat and distributed in South Africa by Takealot.com is not only one of the most cost effective electric heaters currently on the market, it is also easy to setup and use.
As the name indicates, it is a poster similar to one you would hang on a wall. But, plug it in and it turns into a 300 Watt heater. The Poster Heater isn’t designed to heat hallways or large rooms, but rather smaller ones like a bedroom or a baby’s nursery or a dressing room.
It uses radiant heating, which means that it heats up in a couple of minutes and the heat is directed at the objects or people around it, quickly taking the chill out of the air and providing a comfortable ambient temperature.
The other advantage of radiant heating is that it doesn’t dry out the air like infrared or gas heaters. Users also don’t have to worry about their children or pets getting too close to it because, even though it gets hot, it can be touched.
To enter the competition follow the steps below:
Competition entry details:
3. The competition closes on 31 July 2018.
4. Winners will be notified via Twitter on 1 August and Takealot.com will be in touch to organise delivery.
5. The competition is only open to South African residents.