According to tipster WABetaInfo, the bug is prevalent in Brazil. The tipster mentions various user reports from Brazilian WhatsApp users. These messages are usually vcards filled with unsupported characters. It is worth noting that this is not a new bug and it has been around for years. WhatsApp, however, has not fixed it yet. While the official version of WhatsApp doesn’t include any fix, unofficial WhatsApp mods apparently have added ‘Crashcode protection’ to prevent such incidents from taking place. However, we would not recommend using them since your privacy may get compromised. As a preventive measure, it is recommended to set your group privacy settings to My Contacts so that you don’t get added in groups having these crash messages. To do so, open WhatsApp and go to Settings -> Account -> Privacy -> Groups -> My Contacts. If you have received such a message, there are two possible solutions. For those who have connected the device with WhatsApp Web, you could just open the chat from your PC and delete the message. Once you have deleted the message, WhatsApp should function normally. If that doesn’t work, you’re left with no other option than reinstalling WhatsApp. You don’t have to uninstall and install again, though. You can simply go to the app’s settings and clear data for the app to sign in again. While you’re at it, do not forget to restore chat history if you have a recent backup.
