Vector35 / Vector35/debugger

Non-code target shows up when debugging code that has outlined memcpy/mmeset functions

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bug Impact: Medium
Dominant language
C++
Stars
331
Forks
33
PR merge metrics
No merged PRs in 30d

Description

When I debug https://crackmes.one/crackme/66ccb430b899a3b9dd02b07a, I noticed that, at the disassembly level, we can we a few tags for non-code target showing up in the disassembly after we start debugging. This is confusing in the beginning, then I realized these locations all involve the __builtin_memcpy/__builtin_memset functions. And debugging might have changed the status of the backing bytes

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Research direction

Reproduce the issue with the linked crackme and inspect the disassembly behavior around locations involving __builtin_memcpy and __builtin_memset after debugging starts. Determine why non-code target tags appear and whether the backing-byte status changes; done means those locations are represented correctly without confusing non-code tags.

Written by the indexing model from the issue text.

Assessment

Tech stack
cpp
Domain
devtools, reverse-engineering
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
35/100

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