FW 5.18.6+

• AdBreak patched
• No public exploit until SpringBreak

Sources

• NiLuJe’s Open Sesame Index: https://www.mobileread.com/forums/showthread.php?t=320564
• AdBreak thread: https://www.mobileread.com/forums/showthread.php?t=370048
• WinterBreak guide: https://kindlemodding.org/jailbreaking/WinterBreak/
• WinterBreak2 guide: https://kindlemodding.org/jailbreaking/WinterBreak2/
• KindleModding Wiki: https://kindlemodding.org