Questions tagged [x64dbg]
An open-source x64/x32 debugger for windows with UI inspired by OllyDbg.
130
questions
0
votes
1answer
21 views
How to calculate value inside stack segment (SS)
I have an assembly row which the following information:
EBP = 006FFB50
SS = 002B
When I looked on this row:
mov eax,dword ptr ss:[ebp+8]
I assumed that EBP + 8 = 006FFB50 + 8 = 006FFB58.
But ...
0
votes
1answer
29 views
How to view the functions of a loaded library in x64dbg
I am working on a packed file with UPX.
In one of the lines it calls to the value of the address 0xF5222C which is: 0x778057c0.
The debugger auto-completes it to kernel32.LoadLibraryA.
Where can I ...
0
votes
0answers
31 views
What's the reason for a program to crash every time a breakpoint is set in x64dbg?
I know this question may be an ambiguous one and so may not be straightforward, so I apologize for that. Nevertheless, I believe that anti-debugging is responsible for the constant crashing of the ...
0
votes
0answers
42 views
Relative/absolute addressing; RVA, ASLR, the relocation table and patching instructions
I've been trying to learn reverse-engineering for fun, cracking my own dummy games and whatnot and I just learned ASLR is a thing.
I'm now trying to re-conceptualize everything I've read so far ...
0
votes
0answers
39 views
x64dbg execute till next call OR return
I am using x64dbg and I want to know if there's any way to run the code till next Call statement?
I know there is an "Execute till return" option,
but I want to execute till next call ...
1
vote
1answer
36 views
How can I easily convert little endian pointers in hex dumps?
I am tracking down a data structure whose address is inside the second operand:
mov rcx, qword ptr ss:[rbp+E0]
When I look at the value of [rbp+E0] I see the following dump:
21 C4 FC 5E 00 00 00 00
...
0
votes
0answers
25 views
Set a breakpoint for a win command without an address
How to make these columns empty or make a new breakpoint where they are empty? I just need a stop at these win commands (in the summary column), not at a specific address.
I don't know what exactly ...
0
votes
1answer
26 views
How to whitelist an address for breakpoint?
If I have breakpoint on some win function, how to whitelist some address on which I don't want stopping?
Seems that it is needed to use conditions. How?
I use x64dbg, but if you only know a way in ...
2
votes
0answers
36 views
x64dbg break when hex string is loaded
I'm trying to break execution when a string is loaded in memory.
I can´t find the string by using the search for -> string references
So I press Alt + M and press Ctrl + B to search my string ...
0
votes
0answers
28 views
Debug x64dbgpy scripts in vscode?
i've tried to debug a x64dbgpy script using ptvsd and vscode. don't ask me how, but i was able to break into the script using a "remote python attach" session, setting breakpoints and stepping into ...
1
vote
1answer
54 views
x64dbg, breakpoint on write in memory with specific value
In x64dbg, we can set hardware breakpoint on write in memory dump but can we add more codition?
Ex. Set breakpoin on write of value of 2F.
1
vote
1answer
78 views
x64dbg throwing exception
I have been working on finding an overflow in wordpad and i was able to run an exception with an undefined behavior (my point of view). I am using x64dbg (I am not a pro x64dbg) and it shows ...
2
votes
2answers
212 views
Dealing with obfuscated PUSH PUSH RET instructions
I wanted to run an app on a VM but there are PUSH PUSH RETs stopping me from looking at their anti VM code. There is a messagebox when I run it on a VM. I set a breakpoint at MessageBoxA and it gets ...
0
votes
1answer
67 views
How to log CPU instructions executed by program with x64dbg?
How to log CPU instructions executed by program with x64dbg?
I saw x64dbg - see the current position? question, but I can't find the way to log instructions.
Thanks!
1
vote
1answer
58 views
How's this code able to make use of the stack?
I am trying to reverse engineer software to extend its functionality as expected of me. So I don't have the source code with me. Anyways, I am used to seeing codes that start like the one below, and ...
-2
votes
1answer
194 views
Debug and crack .NET executable PE
First of all, i'm trying to learn reverse engineering for testing my codes and that's all and i'm not stupid enough to do illegal things with my knowledge so please don't give me legal advises.
I'm ...
1
vote
0answers
76 views
Recommended plugins for x64dbg
I was wondering, as professional reverse engineers - what would be your "must-have" plug ins? Please give a brief description and say how it helps you and possible drawbacks.
The more you can ...
0
votes
0answers
38 views
x64dbg call function from current thread
While debugging an executable with x64dbg, I want to make a function call (while the executable is stopped on a breakpoint), what I want to do is the same as the following gdb line:
p (void*)freopen("...
0
votes
1answer
72 views
Patching memory
I've successfully reversed and patched an application on windows, but patching the executable on disk triggers a CRC check and prevents it from loading. I've used x64dbg and have the addresses I need (...
0
votes
0answers
48 views
How to display the addresses rather than the labels in x64dbg?
By default, it shows addresses as labels when it can. (call <JMP.&printf>). However, I need it show the actual address itself in the disassembly view. I have looked all around in the GUI, ...
1
vote
0answers
33 views
How to ret with jxx in x64dbg's sciprt
main:
call foo
call bar
ret
foo:
// code
cmp $number, 0
je ret
// code
ret
bar:
// code
cmp $number, 0
je ret
// code
ret
I would like to ...
0
votes
0answers
33 views
Finding out what creates FIFA RTWC 98's main window
I am currently familiarizing myself with x64dbg as a tool for reverse engineering. As an exercise, I challenged myself to try and patch FIFA RTWC 98's executable to force it to run on a windowed mode.
...
0
votes
0answers
48 views
Tracing back the user code section that triggered a message
I have a Windows GUI x86 executable and I have identified, in the .rsrc section, where the error string I want to trace is. Let's assume it is in id=83Ah.
I have set a bpx user32:LoadStringA and then ...
0
votes
0answers
59 views
Reversing WSASend finding functions that called it
I'm trying to make my first DLL calling game functions
What I need is tracing functions that call WSASend, so it will be easy for me to get all functions address to call them from my DLL.
What I ...
2
votes
2answers
94 views
Function Prologue, add esp directive
I need to see how a DLL was written and I am using a x32dbg to do it at run-time. I am a newbie to this reversing stuff, so I am confused with this piece of code:
push ebp ;...
2
votes
1answer
90 views
I can't set a hardware breakpoint on RIP + N-byte after calling NtContinue()
#include <Windows.h>
int handle_exception (EXCEPTION_POINTERS *exception_pointers) {
exception_pointers->ContextRecord->Rip += 4;
return EXCEPTION_CONTINUE_EXECUTION;
}
int main (...
2
votes
1answer
407 views
Reverse engineer Listen to this device on Windows - Reverse engineer Windows when there's no API
I'm writing an Autohotkey script to toggle Listen to this device for my microphone, without interacting with a GUI.
I thought it would be a simple registry key being modified so I used RegShot to ...
0
votes
1answer
71 views
xor eax,3 why does the input change the way it does?
I am new to reverse engineering and I am trying to figure out exactly what xor is doing in this little program. I know if I put any number other than 0 I get a xor eax,3 so if I put in 1 I get 2 if I ...
0
votes
0answers
78 views
About x64dbg find command + Help to unpack a program
The find command in x64dbg(x86),
(found here: https://help.x64dbg.com/en/latest/commands/searching/find.html)
doesn't return anything. For example:
findall 0x00524180, "E8 ????????" returns 50 ...
1
vote
2answers
80 views
Patched Application causes Acces Violation c0000005
I've been working with this application to remove it's trial limitations.
But every byte I change, it throws an acces violation.
Piece of the code:
Original:
003354C6 - 0F85 D3000000 - jne ...
1
vote
0answers
141 views
x64dbg “Use Graph command or menu action to draw control flow graph here…”
When I press "G" in the CPU view of the debugger I often get the following screen:
In what cases can this error message happen? Obviously I can't yet give an exact way to reproduce it, I'm curios ...
1
vote
1answer
74 views
Dump array of char* ASCII text to file? (ollydbg or x32dbg)
This question is similar to: List arrays (de-reference pointers) in Ollydbg
I have an array of pointers that point to character arrays. I followed the above link and can view the ASCII values from ...
0
votes
0answers
300 views
unpacking Armadillo-packed exe on Windows 10
I was trying to unpack the Armadillo-protected target from this webpage Armadillo 4.30a with Debug Blocker - manually unpacking on Windows 10. However, I got another child process spawning again after ...
0
votes
0answers
26 views
What is the “Thread XXXX Stack” Section in x64dbg memory map?
So I am trying to understand how an Aegis Packed Malware works, and from what I am seeing the executable is passing the control to a section labelled Thread 2380 Stack after the EntryPoint. This ...
0
votes
2answers
158 views
How to compare two different executions of the same file?
When i start the program by just double clicking the .exe, it has a certain behavior. This behavior differs when i start the program from running the launcher provided. I’d like to figure out how to ...
2
votes
1answer
179 views
change compare function in assembly and .exe stopped working x64dbg
I'm trying to bypass (crack) a very old software that require license in order to unlock all the features
i was digging in the lines with a little bit of knowledge in assembly
and i found the line ...
2
votes
1answer
235 views
bypass license of very old software, Access violation (C0000005) x32dbg
I'm trying to bypass the license of a very old software that i was using many years ago, now, the company of that software is closed and i can't get a license
so, with a little bit of knowledge in ...
0
votes
1answer
136 views
Nop the string in online games
So i found a string "RespawnTime" in online games and i just edit the string to nop and it worked perfectly, my player is no more waiting to respawn
My question is how is that possible? I just edit ...
0
votes
1answer
309 views
x64dbg: break when a register contains a value
Is there a way to break code execution when a register contains a particular value with x64dbg? I'm not talking about setting a conditional breakpoint at a specific location, but about watching the ...
0
votes
1answer
95 views
x64dbgpy: application unresponsive when trying to automate inside breakpoint callback
When a breakpoint callback is triggered trying to automate the debugger inside the callback causes the application to become unresponsive. x64dbg continues functioning but the application itself doesn'...
0
votes
1answer
651 views
How to use memory address information from IDAFree to set a breakpoint in x32dbg?
I have a DLL paused at EntryPoint in x32dbg. I am interested in examining memory following a specific API call that this DLL makes. I found the API call in the imports section when I open the DLL in ...
0
votes
2answers
291 views
What's ScyllaHide's PDBReaderx64.exe Doing?
I just downloaded the binary of ScyllaHide for x64dbg. According to the instructions, I need to generate an NtApiCollection.ini file by running PDBReaderx64.exe or PDBReaderx86.exe. But I've got a ...
0
votes
0answers
173 views
X32DBG ignores dependent DLL
I have EXE file which calls one specific DLL among other system DLLs. When I change a string value in this specific DLL I can see the changes when I execute the EXE file. For example I can change text ...
1
vote
1answer
102 views
Detailed API call descriptions not available in x64dbg
I am following a RE tutorial, and the guy is using Ollydbg while I use x64dbg... and I don't find all the descriptions in that Olly has, and it's quite annoying !
There is an example from the two ...
1
vote
1answer
206 views
cannot find a string in x64dbg even when using search all strings
I am trying to debug a program for testing but for some reason i can NOT find any strings related to registeration like Registered, Unregistered,Blocked in x64dbg, i can see all these strings in the ...
0
votes
1answer
115 views
How can I navigate to the Disassembly address location?
I'm using x32dbg and I've set a hardware memory breakpoint. It triggers successfully for a specified module and the debugger pauses and a message on the bottom says:
Hardware breakpoint (byte, read/...
2
votes
2answers
146 views
Find a instruction in a binary file (PE) based on a virtual address of a string reference
English is not my first language, so I'm sorry if my text isn't so clear.
I'm trying to program an automatic patcher for a PE binary that should work for multiple versions of this executable. For ...
3
votes
1answer
378 views
Is it possible to view and modify process memory without attaching the debugger in x64dbg?
This functionality is available in Cheat Engine where the debugger won't be attached until you set a breakpoint or explicitly ask for the debugger to be attached. I've looked everywhere and couldn't ...
1
vote
1answer
93 views
Find Retdec Address Range in x64dbg
How do I find this function from RetDec in x64dbg?
// Address range: 0x1017dba0 - 0x1017dbda
int32_t function_1017dba0(int32_t * a1) {
int32_t fileHandle = (int32_t)CreateFileA("\\\\.\\...
0
votes
0answers
321 views
In X64dbg, how can I script a string write to memory?
I find that I can write to memory as
[addr] = value
As given by the documentation at http://help.x64dbg.com/en/latest/introduction/Input.html
And while I could work around my problem as dividing ...
