CVE-2024-21115: An Oracle VirtualBox LPE Used to Win Pwn2Own

This excerpt analyzes a VirtualBox synchronization vulnerability: by flipping a byte (0x23 -> 0x21) the author creates a race between threads holding the VMMDev and VGA critical sections to wake a VGA-waiting thread prematurely. The attempt is unstable — the racing thread changes NativeThreadOwner and causes a SigTrap when the original thread later unlocks the critical section — so the write-up documents an exploit-development effort rather than a confirmed, successful attack.