The Sindhi text bomb, as its come to be known, involves a Sindhi language character that iOS has trouble interpreting. Received via any app that displays text-based notifications on iOS causes the device to crash. Apple is said to have prepared a fix for this bug in its upcoming iOS update (iOS 1.3.4.5) But how can we protect ourselves against this menace with no patch yet available? Luckily, there are a few temporary, albeit inconvenient, steps we can take.”]
Source: https://www.bitdefender.com/blog/hotforsecurity/how-to-block-the-sindhi-text-bomb-on-ios/