iOS 12.4 was jailbroken just recently and includes support for almost every new device. Apple had to quickly react to shut down this vulnerability. I am guessing that iOS 12.4.1 that was just released patches the expolit so that you will not be able to jailbreak on this firmware until another exploit is found.

If you are jailbroken or want to jailbreak stay on iOS 12.4. As of right now we are unaware of any other changes in iOS 12.4.1. We will update this post as soon as we get an official change log.

Here are the direct download links for iOS 12.4.1 should you need them:

• iOS 12.4.1 (Build 16M600) for:
  • Apple TV 4 (AppleTV5,3) — Download
• iOS 12.4.1 (Build 16G102) for:
  • iPad Air (Wi-Fi) (iPad4,1) — Download
  • iPad Air (Cellular) (iPad4,2) — Download
  • iPad Air (China) (iPad4,3) — Download
  • iPad mini 2 (Wi-Fi) (iPad4,4) — Download
  • iPad mini 2 (Cellular) (iPad4,5) — Download
  • iPad mini 2 (China) (iPad4,6) — Download
  • iPad mini 3 (Wi-Fi) (iPad4,7) — Download
  • iPad mini 3 (Cellular) (iPad4,8) — Download
  • iPad mini 3 (China) (iPad4,9) — Download
  • iPad mini 4 (Wi-Fi) (iPad5,1) — Download
  • iPad mini 4 (Cellular) (iPad5,2) — Download
  • iPad Air 2 (Wi-Fi) (iPad5,3) — Download
  • iPad Air 2 (Cellular) (iPad5,4) — Download
  • iPad Pro (9.7”, Wi-Fi) (iPad6,3) — Download
  • iPad Pro (9.7”, Cellular) (iPad6,4) — Download
  • iPad Pro (Wi-Fi) (iPad6,7) — Download
  • iPad Pro (Cellular) (iPad6,8) — Download
  • iPad 5 (Wi-Fi) (iPad6,11) — Download
  • iPad 5 (Cellular) (iPad6,12) — Download
  • iPad Pro 2 (12.9”, Wi-Fi) (iPad7,1) — Download
  • iPad Pro 2 (12.9”, Cellular) (iPad7,2) — Download
  • iPad Pro (10.5”, Wi-Fi) (iPad7,3) — Download
  • iPad Pro (10.5”, Cellular) (iPad7,4) — Download
  • iPad 6 (Wi-Fi) (iPad7,5) — Download
  • iPad 6 (Cellular) (iPad7,6) — Download
  • iPad Pro 3 (11”, Wi-Fi) (iPad8,1) — Download
  • iPad Pro 3 (11”, Wi-Fi, 1 TB) (iPad8,2) — Download
  • iPad Pro 3 (11”, Cellular) (iPad8,3) — Download
  • iPad Pro 3 (11”, Cellular, 1 TB) (iPad8,4) — Download
  • iPad Pro 3 (12.9”, Wi-Fi) (iPad8,5) — Download
  • iPad Pro 3 (12.9”, Wi-Fi, 1 TB) (iPad8,6) — Download
  • iPad Pro 3 (12.9”, Cellular) (iPad8,7) — Download
  • iPad Pro 3 (12.9”, Cellular, 1 TB) (iPad8,8) — Download
  • iPad mini 5 (Wi-Fi) (iPad11,1) — Download
  • iPad mini 5 (Cellular) (iPad11,2) — Download
  • iPad Air 3 (Wi-Fi) (iPad11,3) — Download
  • iPad Air 3 (Cellular) (iPad11,4) — Download
  • iPhone 5s (GSM/LTE) (iPhone6,1) — Download
  • iPhone 5s (CDMA/LTE) (iPhone6,2) — Download
  • iPhone 6 Plus (iPhone7,1) — Download
  • iPhone 6 (iPhone7,2) — Download
  • iPhone 6s (iPhone8,1) — Download
  • iPhone 6s Plus (iPhone8,2) — Download
  • iPhone SE (iPhone8,4) — Download
  • iPhone 7 (CDMA/GSM/LTE) (iPhone9,1) — Download
  • iPhone 7 Plus (CDMA/GSM/LTE) (iPhone9,2) — Download
  • iPhone 7 (GSM/LTE) (iPhone9,3) — Download
  • iPhone 7 Plus (GSM/LTE) (iPhone9,4) — Download
  • iPhone 8 (CDMA/GSM/LTE) (iPhone10,1) — Download
  • iPhone 8 Plus (CDMA/GSM/LTE) (iPhone10,2) — Download
  • iPhone X (CDMA/GSM/LTE) (iPhone10,3) — Download
  • iPhone 8 (GSM/LTE) (iPhone10,4) — Download
  • iPhone 8 Plus (GSM/LTE) (iPhone10,5) — Download
  • iPhone X (GSM/LTE) (iPhone10,6) — Download
  • iPhone XS (iPhone11,2) — Download
  • iPhone XS Max (iPhone11,4) — Download
  • iPhone XS Max (China) (iPhone11,6) — Download
  • iPhone XR (iPhone11,8) — Download
  • iPod touch 6G (iPod7,1) — Download
  • iPod touch 7G (iPod9,1) — Download