EntryBleed: Breaking KASLR under KPTI with Prefetch (CVE-2022-4543)

This report details "EntryBleed," a local information‑leak vulnerability in Linux Kernel Page Table Isolation (KPTI) that lets unprivileged attackers recover the kernel's KASLR base using a prefetch/TLB timing side channel. The author provides a compact proof-of-concept, demonstrates successful results on multiple Intel CPUs and KVM guests, notes assignment of CVE-2022-4543, and suggests mitigation approaches such as randomizing or relocating syscall/entry handlers.