Chaos is the name of the proof-of-concept exploit created by a security researcher from China. The exploit can give someone the ability to remotely jailbreak an iPhone X that’s running iOS 12.1.2 or any previous version. Since the exploit could possibly lead to large scale attacks, the researcher has decided not to release the code. The researcher has commented on the situation saying, “I will not release the exploit code, if you want to jailbreak, you will need to complete the exploit code yourself or wait for the jailbreak community’s release. At the same time, I will not mention the exploit details of the post exploit, as this is handled by the jailbreak community.” Even though Apple has released iOS 12.1.3 to cater some of these issues, 12.1.2 and older are still susceptible to the exploit if it is ever released or figured out.
Users are recommended to update their devices to iOS 12.1.3. Be aware that this does not completely keep the device safe from the exploit, but it is the best precautionary measure to take.