WhatsApp failure due to unreadable message!

M.Sc. Jan Hörnemann

WhatsApp failure due to unreadable message!

The popular Messenger WhatsApp is frequently featured in our blog posts. In today’s blog post, we discuss a WhatsApp failure that could cause the app to crash and require reinstallation. This WhatsApp vulnerability is worth mentioning because it can be triggered by an unreadable message. How this message looks like and how you can protect yourself from this attack is explained in this article.

Unreadable message causes WhatsApp failure

The origin of these unreadable messages, also called “Scary Messages”, comes from Brazil, where according to WEBetaInfo they are a big and widespread problem. The message contains nothing but characters that cannot be read by WhatsApp. If you open such a message from your cell phone, the app will crash immediately. Afterwards the victims have no other option than to uninstall the app and then download it again.

The reason for this reaction on the part of the app is a bug, this bug causes a collection of characters that WhatsApp cannot read to cause the app to crash. The same bug can also be triggered when a virtual contact (VCF) is filled with unreadable characters and is opened in Messenger on a cell phone.


Protection against this attack

Protecting yourself against such messages is not so easy, because basically every WhatsApp user can write to all other WhatsApp users as long as they have the correct cell phone number. However, there are 2 ways to protect yourself relatively well against this attack and thus the WhatsApp disruption.

You should specify that you can only be added to groups by your contacts. Such messages are mostly distributed in groups so that as many people as possible can be attacked with minimal effort. This setting can be found and set under “Account” – “Privacy” – “Groups”.

Another option is to use WhatsApp in the period when this bug exists only via the desktop version WhatsApp-Web. If you open the dangerous messages via the desktop version nothing happens, because the bug exists only in the mobile versions of WhatsApp.

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M.Sc. Jan Hörnemann

Hello dear reader, my name is Jan Hörnemann. I am a TeleTrust Information Security Professional (T.I.S.P.) and have been dealing with information security topics on an almost daily basis since 2016. CeHv10 was my first hands-on certification in the field. With a Master of Science degree in Internet Security, I have learned about many different aspects and try to share them in live hacking shows as well as on our blog. In addition, I am active as an information security officer and have been qualified by TÜV for this activity (ISB according to ISO 27001)