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Tracking memory heap allocations with Pageheap and WinDbg for UAF bugs [v2.4 Technical Discussion]

kernel_komrade
Driver Dev
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4 weeks ago ยท Jul 26, 2026 7:06 PM
#1

To diagnose Use-After-Free (UAF) and heap corruption bugs in complex C++ game codebases:

  1. Enable Pageheap in GFlags (gflags.exe /p /enable target_game.exe /full).
  2. Pageheap places an inaccessible guard page (PAGE_NOACCESS) immediately following every dynamic allocation.
  3. Attach WinDbg.
  4. When a dangling pointer reads freed memory or overflows a buffer by even 1 byte, the CPU triggers an immediate page fault and WinDbg breaks on the exact offending instruction!
ptr_arithmetic
C++ Wizard
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4 weeks ago ยท Jul 27, 2026 12:08 AM
#2

Pageheap is an absolute lifesaver for catching memory corruption bugs before shipping code.

vtable_slayer
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3 weeks ago ยท Jul 27, 2026 7:39 PM
#3

Requires significant RAM but pinpointing UAF bugs in 5 seconds is worth it.