Definition
Plain language
A Windows debugging feature that surrounds each memory allocation with guard pages so memory bugs crash immediately at the offending instruction.
As stated in the literature
A Windows debugging mode that places guard pages around each heap allocation, causing deterministic faults on out-of-bounds accesses or use-after-frees.
Why it matters: Turning subtle memory bugs into deterministic crashes is what makes them findable in the first place.
For example, with page heap enabled, a use-after-free crashes immediately on the bad read rather than corrupting memory and crashing minutes later.
Heard on the show
“They turn on a feature called page heap that makes race-induced corruption produce deterministic crashes at the exact faulting instruction.”Episode 024 — An AI Agent That Found 28 Zero-Days in Windows — And What Made It Work