Apple has released an important update for its operating systems on Monday (19 February) to fix a bug that has been causing apps and devices to crash when a certain character in the Indian Telugu language is displayed. The critical bug first surfaced last week and affected any app that displays characters including Messages, WhatsApp Facebook, Twitter, Instagram, Safari and Gmail.

Once received and displayed in a notification, the character in question caused apps on iPhones, iPads, Apple Watches, TVs and some Macs to freeze up and crash repeatedly as it goes into a bootloop.

Users have been advised not to open any notification or message that might include the South Indian language character.

Still, many trolls have since jumped at the opportunity to exploit the character and use it as a prank against others by inserting the character into their names, posting it on social media platforms such as Facebook and Twitter or sending it via messages.

The bug has since wreaked havoc on a number of users' devices. Apple said it was aware of the issue and working to address it. The bug has already been fixed in iOS 11.3 and macOS 10.13.4, both of which are still in beta testing and will be released later this spring.

The updates rolled out this week include iOS 11.2.6 for the iPhone and iPad, TVOS 11.2.6 for Apple TV, WatchOS 4.2.3 for all Apple Watch models and MacOS 10.13.3 for the Mac.

Apple said the problem identified by an "anonymous researcher" occurred in CoreText wherein "processing a maliciously crafted string may lead to heap corruption". The company said the "memory corruption issue was addressed through improved input validation".

According to the release notes for the iOS 11.2.6, the update "fixes an issue where using certain character sequences could cause apps to crash" and "fixes an issue where some third-party apps could fail to connect to external accessories".

This isn't the first time receiving a particular message or link has caused iOS devices to behave unexpectedly or crash.

In January, a bug dubbed "chaiOS" was discovered plaguing iOS devices that caused the Messages app to crash or your phone to freeze and restart when a user was sent a particular link. It was later resolved with the release of iOS 11.2.5.

In 2015, malicious messages containing a string of symbols and Arabic, Marathi and Chinese characters sent via iMessage or SMS choked Apple's CoreText system and caused the device to crash.