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Im new to reverse engineering, and ive trying Ghidra, IDA (Freeware) and Radare2 with a simple CrackMe, the problem is, both Ghidra and IDA couldnt detect a string while Radare2 (Using Cutter GUI) could figure out the name. I used default analysis for all 3. Is there something im missing ? because even the 'strings' command can actually find the string im looking for.

Ghidra:

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IDA:

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Radare2 (Cutter):

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1 Answer 1

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I don't know the exact length of string. But, few things to note here are as follows:

  1. Ghidra and IDA has a minimum bound on size of string to recover correct type (ghidra has a limit - or lower bound of 5).
  2. This is necessary to avoid any false positives or conflicting types. And recover correct types without marking a pointer as a string. Check out this figure for your reference. Generated using Ghidra automated analysis.

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In Ghidra you can change this limit (minimum is 4) in analysis section.

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  1. Strings command outputs printable characters with minimum size 4 (plus it doesn't use sophisticated type recovery algorithms like ghidra or Ida). I believe that you have a string with length less than 5 and my guess is that it must be 4 to be precise.
  2. strings are usually defined in .rodata section. If you doubleclick on DAT_xxxx, it will take you to the location where that string is defined. There, you will see consecutive bytes bunched together by Ghidra or IDA (as shown in image-1). But, the type is not resolved as a "string".
  3. In Ghidra a quick way to fix this by changing data type of DAT_xxxx label: Right click -> Data -> Choose Data Type -> choose string

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Rereferences:

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    Thank you for taking the time to write such a detailed answer, i changed the data type to string and it worked perfectly and i now also understand how the minimum string's length can effect the analysis, Thank you again!
    – RedZ
    Jan 15, 2021 at 17:55

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