Oh snap! Yap app WhatsApp chaps zap .BAT trap in hack flap

Thinking cap on after security gap tapped


The web version of phone chat app WhatsApp – yes, there's a web version – allowed internet lowlifes to fire off malware at potentially millions of PCs, apparently.

WhatsApp Web runs in your browser, and allows you to message friends and follow conversations just as you would on your mobe. We're told Check Point security researcher Kasif Dekel found a way to sling malicious executables at netizens via WhatsApp Web. Check Point also reckons some 200 million people use the web service.

"To target an individual, all an attacker needs is the phone number associated with the account," noted Check Point's Oded Vanunu in a blog post on Tuesday.

WhatsApp lets you swap contact details between friends using vCards: if you need to get hold of a person, you can ask a chum to fire over a vCard with their phone number inside.

Clicking on the card should start a conversation with this new contact. According to Check Point, it was trivial to send over a .BAT file, all dressed up as a legit vCard, that triggered a malicious executable when clicked on by the victim. To the poor sod being targeted, the booby-trapped message looks like any other message from a pal.

Vanunu explained:

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 utilizing the popular ‘vCard’ format.

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.

WhatsApp fixed the problem on August 27, six days after it was reported by Check Point, which went public with the details this week. ®

Similar topics


Other stories you might like

  • Minimal, systemd-free Alpine Linux releases version 3.16
    A widespread distro that many of its users don't even know they have

    Version 3.16.0 of Alpine Linux is out – one of the most significant of the many lightweight distros.

    Version 3.16.0 is worth a look, especially if you want to broaden your skills.

    Alpine is interesting because it's not just another me-too distro. It bucks a lot of the trends in modern Linux, and while it's not the easiest to set up, it's a great deal easier to get it working than it was a few releases ago.

    Continue reading
  • Verizon: Ransomware sees biggest jump in five years
    We're only here for DBIRs

    The cybersecurity landscape continues to expand and evolve rapidly, fueled in large part by the cat-and-mouse game between miscreants trying to get into corporate IT environments and those hired by enterprises and security vendors to keep them out.

    Despite all that, Verizon's annual security breach report is again showing that there are constants in the field, including that ransomware continues to be a fast-growing threat and that the "human element" still plays a central role in most security breaches, whether it's through social engineering, bad decisions, or similar.

    According to the US carrier's 2022 Data Breach Investigations Report (DBIR) released this week [PDF], ransomware accounted for 25 percent of the observed security incidents that occurred between November 1, 2020, and October 31, 2021, and was present in 70 percent of all malware infections. Ransomware outbreaks increased 13 percent year-over-year, a larger increase than the previous five years combined.

    Continue reading
  • Slack-for-engineers Mattermost on open source and data sovereignty
    Control and access are becoming a hot button for orgs

    Interview "It's our data, it's our intellectual property. Being able to migrate it out those systems is near impossible... It was a real frustration for us."

    These were the words of communication and collaboration platform Mattermost's founder and CTO, Corey Hulen, speaking to The Register about open source, sovereignty and audio bridges.

    "Some of the history of Mattermost is exactly that problem," says Hulen of the issue of closed source software. "We were using proprietary tools – we were not a collaboration platform before, we were a games company before – [and] we were extremely frustrated because we couldn't get our intellectual property out of those systems..."

    Continue reading

Biting the hand that feeds IT © 1998–2022