Questions tagged [decompilation]
Process of translating assembly code extracted from a binary file in a structured programming language, such as C.
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What tricks can I use to manually decompile a set of instructions
ELF Binary takes user input and stores it in loc.buffer address 0x4020e8. Further, the registers going into the instruction set are
eax
ebx
ecx
edx
esi
length of user input (min length is 3)
0
...
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IDA Pro Flow Chart and Decompiler Doesn't Work on Single Instruction text
Recently I got a program that has two colors of .text segment, one is black and the other is brown:
While the flow chart and the decompiler work well on black part, they are both disabled on the ...
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Is there a way to run arbitrary code on a vtech Nitro Vision?
Note: If this the wrong place to ask the question, please redirect me to the appropriate stack exchange and/or subreddit. I just figured reverse engineering is my best bet since it's kinda what I'm ...
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Find out what is this binary database entry and what format it is
the following varbinary "BUFFER" of a database entry is for an article.
FIELD_0 is in plain text and the item name is "1", which I created with the item management software.
[...
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Which encryption method has been used?
Anyone please can you tell me which method used to encrypt this kind of codes?
im really confused, that would really helps me.
This encrypted data created by a PHP.
Ibª„bÏ}◊Kì-yNî˜>Efi¶ØÁÇ_^§ ...
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How to interpret this __ctype_b based predicate?
I am getting this simplified function from the decomplication results of Ghidra, and I am having a hard time interpreting what the predicate would evaluate to since I do not have access to __ctype_b ...
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How to list all references to memory from selected memory region in ghidra?
I want to find all peripherals used by firmware dumped from embedded device. I loaded SVD file to add registers into memory map. Now I can find a peripheral in the memory region and check if there are ...
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Extracting contents of unknown file format
I would love some help on working with this file format.
I have this archived file from this abandonware game that I like to mess around with, and I have tried all sorts to try and expand it to ...
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Are there websites for reverse engineering challenges similar the programming challenges? [duplicate]
As a developer, reverse engineering has always fascinated me. It amazes me to see what some people can figure out just from a dump of assembly code, and I would like to become better at doing the same....
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Decompiling and Recompiling APK leads to crash using Apktool
Decompiling and recompiling an apk causes it to crash. My goal is simply to insert a method into smali code that prints a stacktrace, but even decompiling and recompiling with no changes causes the ...
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Dumping .NET Dynamic Methods
I have a .NET exe that creates DynamicMethods whose bodies are built from a byte array and later called. I'm able to access the array, and even to disassemble it "raw" starting from the ...
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How to see the src of a Node.exe
Long story short, my friend sent me some scripts a while ago and lost a lot of his old source code and I wanted to see how it works but it's compiled into a node.exe (Node.js: Server-side JavaScript). ...
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How to Convert given set of Assembly-Level Instructions to High-Level Language Code?
As I am working on malware analysis, I got stuck in a place where I have to change the given set of assembly-level instructions to high-level code. Example:
Assembly Level Code
mov ebp, esp
...
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IDA Pro maps wrong variable for offset
I hope there is a proper way to fix my issue.
Here's memory layout:
.data:004F3D10 char * * gTownObjNames dd offset aMage ; DATA XREF: townManager::SetupTown(void)+245↑r
.data:004F3D10 ...
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Reverse-engineering a 90s CNC machine (FORTH like) firmware
Here's an undertaking I'm currently in, and would absolutely love someone to assist more directly. I'll list the subjects that I would greatly appreciate more knowledge within. Know anything about one ...
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How do I Decompile .Pyd file made with python, cython and pyinstaller 3.6
I created an app in 2018 with python and then used Cython and pyinstaller v 3.6 wondering how to decompile it. I have tried uncompyle6 + pyinstxtractor however this only works for python files not ...
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Can I get a valid source code from this assembly?
I've used the IDA 8.0 Demo to retrieve (from a .DLL) the assembly code, such as:
; code
pxor xmm0, xmm0
ucomiss xmm0, xmm1
ja short loc_67F31600
movss xmm2, cs:...
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1
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Decrypting .toc file
So I have a few files from a game on my pc, most of which are .toc files
I believe this means they are a "table of contents" as the ending suggests, but my attempts to read them have been ...
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How to correct decompiled output with `in_stack_` (ppc BE)?
So I have something like:
*************************************************************
* SYS_DRAW_BATCH_RUNS_DATA::Set(matrix4 const*, RECTF con ..
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Decompilation output modification in IDA Pro
I am trying to modify cfunc AST from
If (a1 && some_func_ptr) {
some_func_ptr();
}
To
if (a1) {
some_func_ptr();
}
But I constantly get INTERR 50683 error. I tried
new_item = idaapi....
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Crackme assistance - unknown function [closed]
i have a problem about a crackme that my friend sent me for a bet. I solved most of it but i am stuck with this function. I can't even understand what the function is trying to do. Please help.
images ...
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Ida Pro can't decompile big function
I tried to decompile (Pseudocode) a big function into binary with Ida Pro 7.7 but I got error :
The graph is too big (more than 1000 nodes) to be displayed on the screen.
Switching to text mode.
(you ...
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Missing mnemonics '??' in Ghidra Assembly Code
I was just trying to google and search for "??" Ghidra with no luck.
I am trying to understand what the following questions mean in this Binary (meant for SuperH2 SH-2 processor) which is ...
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1
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Python or C for a Qt application and security against reverse engineering
I actually have two choices : C or Python to create my application.
On my application users will need a key (on start) to access it, the key will be verified with an algorythm on the user's computer. ...
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Borland C++ 3.0 - Which code might produce this strangely convoluted ASM sequence?
I'm reverse-engineering a DOS binary that was compiled with Borland C++ 3.0, and I'm trying to create C code that will produce the same assembly as the original when compiled with the same compiler. ...
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STM32 - Disable Voltage Check
I'm planning to edit the binary Firmware for an STM32F030K6T6 ARM microcontroller used in the IKEA Fyrtur blinds. In particular I'm trying to
disable the Voltage check (allow alternative power source)...
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How to utilize `FillOutStructureCmd`?
Basically I'm extending the CreateStructure.java plugin so it iterates all functions and tries to automatically create structures on all variables.
It looks something like this:
public class ...
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Where can I find the encryption algorithm for this POST request in an Android APP?
I have an Android app for which I need to mock an API call outside of that environment. I successfully killed the certificate pinning on this app with Frida in order to access the URL and more, but ...
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Understand a function within Hermes byte code
The Android app I am looking at uses React Native with the Hermes JS Engine. This generates a index.android.bundle binary that contains Hermes JS bytecode.
I was able to disassemble the binary file ...
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Decompile obfuscated jar file
Tried java-deobfuscator and other things, detect said it was allatori protected so tried the relevant transformers but to no avail.
Please can someone help, I'm happy to tip for your help :)
https://...
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Getting helpful information on classes in Ghidra?
I'm an intern at an engineering firm that's being contracted to decompile some ELF32 files on an ARM device compiled with GCC. Currently, we're using Ghidra, but no one at the firm (including me) ...
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What change to the source code would produce an LT compare rather than an OLT compare in MIPS assembly?
I need some help reverse engineering a function in MIPS assembly. It was compiled for the PlayStation 2's EmotionEngine CPU. My goal is to produce a matching decomp of the function; it is the proof-of-...
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Deobfuscator and decompiler for .NET [closed]
Which are the most common and useful deobfuscators and decompilers for .NET .dll files?
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How to reference an address set by 2 instructions in Ghidra
I encountered the following 2 instructions while reversing Tricore assembly:
These 2 instructions load the final address: 0x804A9474. Where a global symbol resides.
Is there a way to hint Ghidra the ...
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Harden C++ against decompilation
I have a small C++ program that contains a "secret" string that must be hard to find in the object code, e.g.,
#include <iostream>
int main() {
std::string a = "super-secret-...
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Custom IDA Decompilation Coloring
Is there a way to customize the coloring of IDA's decompiled code?
IDA -> Options -> Colors -> Syntax doesn't seem to affect the coloring of decompilation.
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Invalid memory access and class check in operator implementation
Say I have the following disassembled function, taken from my favourite 32 bit DLL that was compiled with an old version of MSVC:
mov eax, ecx
mov ecx, DWORD PTR [eax+4]
cmp ecx, CAbstractBlitObj::`...
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How to make Ghidra don't brake mid token with triple dots?
So I was scraping the Ghidra disassembly output until I realized that some of my tokens are ...
Anyone knows how can I configure this up so Ghidra doesn't limit the output of it's disassembler (...
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Philosophical and procedural question - Process for using x64 inline assembly in recovering source code
I am assuming this should place be appropriate for what I want to ask. I want to ask more of a philosophical and procedural question because I don't want to try things that have been tried and spend ...
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Is it possible/feasible to decompile a program written in C++ to C?
I've not seen a lot of material on this. I've seen people attempting to bring a C++ program back to C++ code, and claiming how hard it is, but C code from C++ program? I don't know.
If it is possible, ...
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How to define "code" variable type in Ghidra
Of all the confusing parts of Ghidra, I'd like to ask about the "code" keyword. A similar question was asked here. However, I am not asking what the keyword is, but how to interpret/define ...
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IDA decompiler syntax: for function int __usercall sub_45BD46@ <eax>(char a1@<bl>, int a2@<esi>, int a3)
I have a function with the following header sub_45BD46@eax(char a1@bl, int a2@esi, int a3), my question is: I am right that sub_45BD46@eax means the result value is in eax?
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Decompiling a Node.js application compiled with nexe
Someone have sent a Discord token stealer and out of curiosity, I would like to decompile it, just to get some info about the attacker.
Judging by folders created in my user directory, multiple ...
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identify the functions of stripped binaries
As far I know that stripped binaries when we decompile it we can't know what most of functions (sub_XXXXXX) really do becuase they are not part of the binary's symbol table, so the names are ...
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Re-analyse HexRays decompiled output
I have analysed a large library in an older version of IDA and want to upgrade. I have marked lots of functions as "decompiled" and changed their function signatures.
How do I automatically ...
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Useless instructions in a compiled getter
This is the second time I see this kind of function today :
.text:00000000000010B0 sub_10B0 proc near ; CODE XREF: sub_1120:loc_1143↓p
.text:00000000000010B0 lea ...
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Hex-rays decompiler incorrect logic
I'm practicing reverse engineering in IDA and I created an example application in Visual C++ to practice working with classes/structs and the decompiler output seems to be incorrect - I would like to ...
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Decompile a NodeJS compiled program maybe by NEXE
I recently got idiotly scammed one of my discord account but kept the malware in case.
Curious, I would love today to break into the executable to fetch any information about the scammer.
I decompiled ...
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The way to determine how the decompiled constructor is structured
I have the following constructor decompiled by Ghidra, i.e. Game. I know some of the functions, which are part of that constructor. And thus I have created my interpretation of that structure. But I ...
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What is the correct argument for the disassembled function / constructor?
I have the following code disassembled by Ghidra. It first initialises the local variable of the particular type (local_68) and then passes it to the constructor. The variable seems to be initialised ...
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