Questions tagged [obfuscation]
Concealing the nature of how things truly function or work.
1
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0answers
79 views
Mysterious chunk of code in IOLI crackme0x06 challenge
I've been struggling to understand a very strange piece of x86 assembly code from the IOLI crackme0x06 challenge.
Context
But first of all, here is the context : I've successfully cracked the ...
0
votes
0answers
47 views
Reverse engineering .NET malware - iloveyou.exe
I have a .NET malware sample whose dynamic behavior I understand. It is also packed.
de4dot identified the obfuscator as .NET Reactor, so I used de4dot to de-obfuscate it. However, after de-...
1
vote
0answers
39 views
How to choose a .NET software protector which will have a small impact on run-time performance speed? [closed]
I am writing a .NET software which is doing calculations and drawing in real-time i.e when the user is moving the mouse. I want to protect this software from being reverse engineered and restrict its ...
0
votes
1answer
427 views
How to deobfuscate native Android library obfuscated with OLLVM?
When I load the binay in IDA, all I can see are loads of .datadiv_decodeXXX... functions and this is because of OLLVM. I know it is possible as a Chinese article I found said they were able to ...
0
votes
0answers
32 views
Replacing a function call with it's result in a script
I'm working with a heavily obfuscated Autoit malware script and one of the major problems is that almost all variables and lines of code are obfuscated by a custom function.
The problem is that this ...
1
vote
1answer
110 views
Does a symbolic disassembler exist?
I would like to know if there are disassemblers based on a symbolic analysis, I'm beginner in RE, but I think that a disassembler based on symbolic techniques can be very interesting and could ...
1
vote
2answers
145 views
Jump in the middle trick
I'm reversing a program that "hides" some instructions using the jump in the middle trick. This trick is a jump to a middle of an instruction, whereas the real address actually contains another opcode....
1
vote
1answer
152 views
What's this obfuscation technique?
I'm reverse-engineering a particular dylib on Mac OS X. The dylib is highly obfuscated, but I suspect it's from some well-known technique that I'm not aware of.
I'd like to describe it in the hope ...
6
votes
1answer
341 views
Simplifying assembly
I'm analysing some binary trace, it's pretty much obfuscated. What I need to do is to understand work flow of its alghoritms. However I cannot find any reliable tool which would help me with that.
I ...
1
vote
1answer
303 views
Analyzing and deobfuscating complex JS code [duplicate]
I am looking to reverse engineer a very ugly piece of JS found here.
As far as I can tell, this script generates and sets some cookies on my browser that identify it on the site. Deobfuscating it ...
1
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0answers
174 views
C# Hidden Method through transparent proxy object?
I'm dealing with an interesting form of obfuscation. A C# program I am reversing has a central API, let's call it "Central API". This Central API has several functions that aren't exactly defined.
...
7
votes
2answers
315 views
Why do obfuscators remove line numbers, and can I safely leave them in?
Application security engineer here. When we compile our java code, we obfuscate it using KlassMaster and have it remove line numbers (see KlassMaster docs) because of a handwavy explanation "it makes ...
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1answer
234 views
What is the difference between stripped binary and obfuscated binary
I want to know the difference between stripped binary and obfuscated binary.
1
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0answers
568 views
Can de4dot deobfuscate Dotfuscator Professional?
I ran de4dot on a Xamarin app obfuscated using Dotfuscator Professional. However, there's still the random switches and strange ints everywhere. Can de4dot decode this? If not, is there another tool ...
4
votes
3answers
170 views
Obfuscated code analysis - can unused variables be ignored?
I am analyzing a malicious javascript. The code is encoded and obfuscated in a way that I did not manage to even partially deobfuscate yet and it is filled with long strings. In order to simplify the ...
1
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0answers
48 views
Missing Map from Java Native Method to C Code
When writing a C implementation for a native Java method in Android, the rule is to name the C function according to the convention "Java_com_...". But I encountered an APK in which there are no such ...
1
vote
1answer
1k views
Is deobfuscation of my javascript code hard or easy?
I am trying to protect my app code from theft. Since most of it is written in javascript I had to use many obfuscation techniques to make it incomprehensible.
I have written a very small piece of ...
2
votes
0answers
236 views
Obscure router refuses to flash OpenWrt
This is a very obscure Chinese router from a brand called Wavlink. It's the Model: WN529R2/WN529R2P. It's web interface was pretty limited and wouldn't allow firmware modifications.
I found GND/Tx/Rx/...
3
votes
2answers
147 views
Why doesn't this retn instruction return from the function?
I disassembled an exe file on Windows with IDA and saw this function prologue:
I see that when the retn executes instead of returning it jumps to sub_1314cba4.
Why doesn't the retn instruction ...
-3
votes
1answer
3k views
How do I decode this JavaScript code? [duplicate]
Each file starts with the same function:
(function(_0x128f83, _0x1ae5b9) {
var _0x1b5471 = function(_0x339be5) {
while (--_0x339be5) {
_0x128f83['push'](_0x128f83['shift']());
...
1
vote
1answer
259 views
Map an obfuscated javascript file to the original
Among other approaches, there are ways to "prettify" obfuscated javascript. But most of such approaches are geared towards someone trying to understand code that's not their own (e.g. from a website, ...
0
votes
2answers
566 views
verifyError in youtube android app modification
I try to decompile youtube android application and modify it but when I build the application and install on a virtual device faced with below error:
E/AndroidRuntime(1782): java.lang.VerifyError: ...
3
votes
1answer
233 views
IDA pro obfuscation instance
I have tried all the I have learned so far to figure out how to deal with this instance of obfuscation.
So far I understand that an opaque predicate is present, causing an unconditional jump to one ...
3
votes
1answer
351 views
Deobfuscating overlapping x86 assembly instructions
I'm trying to solve a reverse engineering challenge (http://crackmes.cf/users/beatrix/beaba/) and am having trouble with the obfuscation. Below is a piece of code that gets executed almost immediately ...
3
votes
3answers
1k views
Exe protection by TLS callback, trying to understand the behaviour
I have an app, obfuscated by FSG protector. When i tried to unpack it, the first thign that i had is, when i start the process with the debugger/or attach debugger later, i immediatly receive ACCESS ...
0
votes
1answer
382 views
ARM ELF Obfuscation [closed]
Metamorphic is a technique to obfuscate a binary and change the opcode sequence and create new samples with same functionality. In my case, I have some elf binary of ARM processor type and their ...
1
vote
2answers
195 views
reverse javascript crackme encryption method algorithm
This crackme contains a text input element on the screen and a button to validate
The value you enter is set into _inputValue, afterwards you click on a button, the function executes, in the last ...
1
vote
2answers
375 views
Techniques to hide a process (procmon)? [closed]
On Windows, how would one go about hiding procmon from another process? What techniques/terms would I be searching for?
1
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0answers
670 views
de4dot and Dotfuscator: IL looks different, not DotPeek decompiled code
From the obfuscated to the deobfuscated assemblies, IL code looks different using ILDASM; however, DotPeek decompiled C# code looks exactly the same for both. Any clue why?
The obfuscation software ...
0
votes
1answer
137 views
How does the different types of executable packing work?
Reference to this thread: What are the different types of packers?
Q1: How do packing methods like compression, protection, and encryption work, how do they differ, and which is more secure?
Q2: ...
1
vote
0answers
83 views
How to hide / obfuscate the function of an IC?
Let's say I have an IC (integrated circuit) and I want to hide it's function. What would be best practice to do that?
Removing the markings with sandpaper or acid?
(E.g. atmega328, ATtiny85,... ) ...
8
votes
2answers
733 views
Is there a name for this kind of “obfuscation” for the machine code from C++?
I was trying to reverse engineer an android ndk (arm) using ida pro on a static analysis. However, it appears there are a lot of useless jumps to the same place and with random values set to R1 to ...
0
votes
2answers
519 views
Android App's hardcoded local keystore password r3versing
Novice Android security researcher here. Recently I was tasked with the task/challenge of exposing a certain app's hardcoded local keystore password.
I've decompiled it with JEB2 and obviously within ...
0
votes
1answer
84 views
What do the unusually named packages and files usually mean?
When decompiling an apk with apktool, the classes.dex file is decompiled into folders smali_classes#, and sorted their respective packages. I recognize some of the files, as they are mentioned in ...
2
votes
1answer
84 views
Unkown Swap Encoding
I'm trying to figure out this encoding in malware.. All I have are the static strings..
I was able to figure one out so there is plaintext on one:
e-snAetgrU$
translates to
$User-Agent
Here are ...
2
votes
1answer
227 views
Distribution of malware obfuscation types
There are several statistics and numbers out there of current malware families and their distributions.
However, I'am looking for statistics which shows the distribution of malware differed by their ...
1
vote
2answers
173 views
Obfuscation by changing the order of a malware behaviour
I know that there are some obfuscation techniques which can lead to slowing or even failing the detection of malware when static analysis is used.
However, is there a similar technique that changes ...
1
vote
0answers
275 views
Discovering byte array obfuscation function
I'm in the middle of reverse engineering SafeNet (formerly Rainbow) iKey 1000 USB dongle protocol, in order to create Linux driver for it. I'm using Windows as guest in virtual machine on Linux host ...
1
vote
1answer
3k views
How to obfuscate x86 assembly code?
For my project, I am performing a kind of checksum operation on a portion of code to protect it and therefore do not want its template to be easily visible and therefore need obfuscation.
I have ...
1
vote
1answer
611 views
I'm decompiling an apk file to learn how the creator designed the UI for their app. Are these layout files obfuscated?
I'm new to decompiling apps. Most of the apps I decompile aren't very popular, so obfuscation hasn't been a problem yet. I'm not entirely sure what obfuscation looks like. The current app I'm looking ...
2
votes
1answer
1k views
Any good deobfuscators for java?
So I've built an obfuscator for java source code, would anyone know if there is any good deobfuscators which i could test how well my obfuscator is?
I know there are many deobfuscators out there, ...
2
votes
2answers
460 views
Unpacking NSPack v 2.9 based malware to get OEP
recently i am analyzing a malware which is packed with NSPack.
when i am trying to unpack it using this blog link,i landed over two instruction PUSHFD,PUSHAD in ollydbg.
so i put a breakpoint on the ...
1
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0answers
63 views
Java source code deobfuscator? [duplicate]
Does anyone know of any source code deobfuscator in java?
I'm currently writing an obfuscator for java source code and I want to test how well I have made it with an deobfuscator.
5
votes
1answer
1k views
Obfuscated AES decryption assembly
I have recently been sifting my way through a whole load of assembly to try to identify how a program is decrypting some data. Thus far I have identified how the IV is extracted, that the IV is 16 ...
2
votes
0answers
332 views
Jar reversing: Can't open as zip file nor open it with common decompilers
I'm pentesting a JNLP application composed by several .jar files. I'm able to decompile with jd-gui every 3rd party library included in it, but the main .jar coded by my client.
So after running JD-...
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votes
1answer
3k views
How to deobfuscated javascript?
How to deobfuscate javascript file, i have a javascript code are deobfuscate .
Code: http://pastebin.com/zFH2GidN
Help me and thanks you.
0
votes
0answers
71 views
Encrypting and packing at functional boundaries for obfuscation
I am interested in software obfuscation techniques. I found your excellent summary of obfuscation in order to avoid (as possible) reverse engineering.
One of the proposed technique you quoted:
...
1
vote
3answers
1k views
How does PeID calculate entropy?
I'm curious about the entropy field value that shows up when a binary is dropped into PeID. Does someone know how it arrives upon this value?
1
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2answers
571 views
Debugging Win32.Upatre - why does Ollydbg fail to analyze this?
So I've been looking at this thread - Where can I, as an individual, get malware samples to analyze?
And grabbed myself a binary sample of Win32.Upatre from Halvar Flake's blog.
I started analyzing ...
1
vote
1answer
3k views
Tools for automated deobfuscation
To evaluate different Java obfuscators, I want also consider if the obfuscators use preventive techniques against common tools used for automated deobfuscation.
Therefore I plan to obfuscate a test ...
