Apple also released updates for macOS 10.13.3, tvOS 11.2.6, and watchOS 4.2.3 , these updates are just patches to fix the “Telugu” bug which causes apps like messages to crash when a single character of the Telugu language is sent to them, Telugu is a Dravidian language native to India.
These updates also fix other bugs, including a macOS bug which displays messages in the Messages app in the wrong order.
The bug surfaced on a bug report site called Open Radar just over a week ago, and is as simple as sending a Telugu language character to the device which causes the device to crash.
Apple’s security update outlines the bug as a “memory corruption issue” caused by “processing a maliciously crafted string”.
The “Telugu” bug is the latest in a series of “text bomb” bugs to affect iOS devices. These updates are a quick install via Settings > General >Software Update, however the macOS update via the App store requires your Mac is restarted.