Questions tagged [unpacking]

Reverting (statically or dynamically) the effect of a binary packer: recovering its original structure and code by removing compression, encryption, protections features..

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40
votes
3answers
19k views

Unpacking binaries in a generic way

I find that more and more often binaries are being packed with exe protectors such as upx, aspack etc. I tried to follow a few tutorials on how to unpack them but the examples are often quite easy ...
19
votes
4answers
6k views

How common are virtualized packers in the wild?

I'm just getting into the RE field, and I learned about virtualized packers (like VMProtect or Themida) in a class about a year ago. How often is malware in the wild really packed with virtualized ...
17
votes
4answers
3k views

How can you reliably unpack a Windows driver manually?

When you unpack manually a Windows user-mode executable, you can easily break at its EntryPoint (or TLS), then trace until you reach the original EntryPoint. However that's not possible with a packed ...
15
votes
2answers
2k views

Decoding an unknown image format with “DREK” signature (*.drk)

There are some unknow images, which I would like to decode to RRGGBBAA format. It was a really hard work, but at the moment I can somewhat understand, that which part of the binary is responsible for ...
10
votes
1answer
816 views

What is import reconstruction and why is it necessary?

When reading about unpacking, I sometimes see an "import reconstruction" step. What is this and why is it necessary?
8
votes
2answers
949 views

Automated Static Unpacking Binaries

I am reading the paper Automatic Static Unpacking of Malware Binaries (Kevin Coogan et al.) with the goal of trying to reproduce the given experimental results (with Hybris-C, MyDoom.q, tElock, etc), ...
7
votes
1answer
3k views

Unpack Billion 5102 firmware

I'm trying to unpack this firmware image but I'm getting some issues understanding the structure. First of all I have one image which I called firmware.bin, and the file command shows me that it's a ...
7
votes
1answer
2k views

Zte Reverse engineering config.bin file problem

I just got a Zte ZXHN F660 GPON ONT Wireless router with my optic fiber internet provided by my telecom provider. My first discovery was that the eth Lan ports are bricked wich means I can only use ...
6
votes
3answers
5k views

unpack Clear spot .bin firmware update

I am trying to unpack a clear spot firmware update The firmware I am trying to reverse can be found on the download page of the vendor I have used the fwtools to unpack the firmware as described on ...
6
votes
4answers
2k views

Unpacking binary statically

Say I have a binary that I'm not able to execute (for example it runs on some device that I don't have one of), but I can disassemble it. I can get the docs on the architecture. (It's MIPS little ...
6
votes
3answers
3k views

Can't access process memory when dumping

I'm trying to analyse a piece of malware and after finding the OEP I'm having trouble dumping the process. Using LordPE (and IDA) I get an error saying "Couldn't grab process memory", I searched for ...
6
votes
2answers
2k views

How are obfuscators detected?

I'm guessing that tools like PeiD detect packers by looking for signatures inside the packed binary and by measuring the entropy. Is there any other work that tries to determine if a binary is ...
6
votes
2answers
4k views

How to find file compression or obfuscation type

The program I'm trying to decompile uses several supporting files: somesound.mp3 someimage.jpg etc.. The files are all located in the file system, not embedded into the exe. The files are used at ...
6
votes
1answer
2k views

Any idea how to decode this binary data?

I have binary data representing a table. Here's the data when I print it with Python's repr(): \xff\xff\x05\x04test\x02A\x05test1@\x04\x03@@\x04\x05@0\x00\x00@\x05\x05test2\x03\x05\x05test1\x06@0\x00\...
6
votes
2answers
1k views

Is there any tool which parses ollydbg run trace?

I'm currently working on a tool to automate several actions which relate to unpacking software. I would like to use the run trace of Ollydbg (1.10 preferred since it has many antidebug/usage/etc ...
6
votes
0answers
659 views

Audio file compression identification

I've been working on reversing file formats from the game of star wars episode 1: the phantom menace. I have managed to extract the audio files from the .lab file in which they were contained. I ...
5
votes
1answer
9k views

Unpacking a Themida packed x64 executable?

Before we continue I'd like you to keep in mind I'm relatively new to unpacking executables. So I have a few Recently I've been trying to unpack an executable (x64 architecture), aka find the OEP and ...
5
votes
2answers
5k views

How to unpack files packed with multiple packers?

As I am just getting started in RE, I've mostly faced files packed with a single-layer of packing , such as UPX, ASPack, etc. Unpacking these protections is fully documented online. The problem ...
5
votes
3answers
886 views

Linux protectors: any good one out there?

I know no one that works as of today (i.e., kernels not way too old) and I wonder if anybody found or knows any protector for Linux either commercial, open source, used in malware, etc...
5
votes
2answers
674 views

Reversing Self-Modifying Malware

recently i got my hands on one sample that self-modifies its .text section. So, I placed a breakpoint on .text section on write operation and then continued. I found out that it zeroes out the .text ...
5
votes
2answers
315 views

What are some ways in which virtual machines make native static and dynamic reversing of a binary more difficult?

It is practically common knowledge in reverse engineering that trying to use a native debugger or disassembler on a "VM protected" or virtualized program is much more difficult to analyze. However, I ...
4
votes
4answers
12k views

Finding OEP in a VMProtect v3.0 protected malware

I've been trying to reverse engineer a malware that has been packed with VMProtect v3.0. My first instinct was to google an automated way for this and I found a script. Unfortunately the script to ...
4
votes
2answers
1k views

Why to dump precisely at OEP while manual unpacking?

What is the exact reason for dumping a process when the Program Counter is at OEP? I haven't found a decent answer. This Link says: In order to identify the IAT structure, Import Reconstructor ...
4
votes
2answers
4k views

Reversing Hisense TV Firmware

I am looking for methods to get root on my Linux smart tv. Anyone have any ideas, in order to try extract the kernel config. Hisense is no help when asking for GPL source. I ran metasploit against it ...
4
votes
2answers
2k views

How to extract the filesystem from a I240w-A firmware

I am trying to extract this ONT I240w-A firmware and binwalk reports some LZMA compressed data (dump below) but the fact the all of them read "uncompressed size: -1 bytes" makes me suspect they are ...
4
votes
2answers
288 views

Need help in figuring out checksum used in this small wireless packet

Need help in figuring out the checksum used for this small data packet. Packet is 48 bits long, I already have figured out most of the bits. Least 8 bits change even if there is a single bit change in ...
4
votes
1answer
1k views

Can a debug-apk be reverse engineered to make it a release-apk?

I am making a system in which the users can create Android applications. I want them to give an option to download a debug apk so that they can try it out first. After that, they have to pay for it to ...
4
votes
1answer
817 views

Unpacking a Digi Connect ME bin file

I'm working with a Digi Connect ME serial to Ethernet bridge, which runs a "Plug and Play" firmware by default. The specific product page is here. The part number is DC-ME-01T-S. It appears to be an ...
4
votes
1answer
274 views

Decoding LZSS buffer lookup indices

I'm working on unpacking a camera firmware file which consists of various sections that I am able to correctly split and validate. One section within this file is additionally compressed with a form ...
4
votes
1answer
4k views

Unpack files from executable

I have an exe application that contains three files packed in it. I know how those files were named before packing, I have around 80% of packed files and some of main executable file binary code. I've ...
4
votes
2answers
3k views

IDA Pro failed to display the program in graph mode

i am a complete beginner with IDA and I have just tried to follow a tutorial on how to unpack UPX. In the tutorial IDA looks like this: When I try to get the graphical view like in the tutorial an ...
4
votes
2answers
601 views

Getting empty files using firmware modification kit

im having trouble to extract a file system of a ZTE zxv10 h201 router. Im a beginner in reverse engineering so I am probably doing something wrong. This is what I have done so far. I got the admin ...
3
votes
1answer
420 views

How can I determine if a piece of code is an encryption algorithm?

I am trying to reverse engineer a malware, and came across a piece of code that I suspect is an encryption/decryption procedure, however I do not know for sure. I can recognize that it extracts its ...
3
votes
2answers
12k views

Why my Resource Hacker doesn't work with some .EXE files

I use Resource Hacker Application for Reverse Engineering purposes, I've cracked 3 softwares by using this software, but it doesn't grab all .EXE, .DLL files. sometimes It says, This is not a valid ...
3
votes
1answer
2k views

What are the steps, to extract an unknown archive file in this case?

I've never did something like this before, but I have programming experiences. There are two files: data00.big and data01.big, which I would like to extract. I've tried Dragon Unpacker, which can ...
3
votes
2answers
12k views

How to force IDA to analyze a packed exe after the program has unpacked itself?

I know it is a very newbie question and sorry about that, but I can't really find any way how to make IDA analyze the code after the unpacking was done. What I mean is that when I unpack an exe and ...
3
votes
1answer
945 views

UPX packing/unpacking information preservation

If I pack an executable using UPX and then unpack the executable using UPX -d, the executables are not the same. I understand techniques for unpacking executables that are packed using UPX, but I was ...
3
votes
1answer
468 views

Animal Crossing: Pocket Camp .zdat File

Hello I am trying to obtain the music from the new game Animal Crossing: Pocket Camp. The music is contained in files like these: https://download-cdn-ac-pocketcamp.akamaized.net/assets/...
3
votes
2answers
7k views

Packed PE-file, where to start?

I'm new to reverse engineering, so maybe it's an easy question but not for me). I've got .exe file which is somehow packed. When I open it with IDA, I got warning that file was packed or modified, and ...
3
votes
1answer
4k views

Set memory breakpoing on access on a section in IDA

Is there a way to set memory breakpoint on Access on IDA in Win32 debugger... like we do in Olly from the memory window ? I tried to do that with the example "UnPackMe_NoNamePacker.d.out.exe" in 20th ...
3
votes
4answers
9k views

Unpacking and dumping using ollydump

I am trying to learn how to unpack a malware. I am trying this with ollydbg. However, when I try to dump the unpacked using ollydump plugin. It prompts the error "Bad DOS signature!!". Could someone ...
3
votes
1answer
2k views

What are indicators for hitting the OEP?

for me, it is sometimes difficult to decide if I have hit the OEP when I try to manuelly unpack it. Especially in cases, when it does not begin with the standard function prologue. For example: I ...
3
votes
2answers
285 views

Manually unpacking DarkTequila, stumped. Can anyone help?

The malware is packed w/ UPX - can see 0/1 in sections. Sure, I can can a tool or even use UPX -d -o flags .exe to create an unpacked copy with a >97% ratio, however I want to MANUALLY unpack it to ...
3
votes
1answer
840 views

How to unpack Inno Setup bundles with Arc+SREP data?

I've stumbled upon Inno Setup installer with additional separate Arc archives (commonly with .bin extension) that I was unable to extract using normal methods: the installer didn't work for an ...
3
votes
2answers
3k views

Fixing import table of unpacked DLL with ImpREC : ImpRec throws “invalid OEP!” error

I am trying to unpack a DLL and fix the import tables with ImpRec. However, I am stuck with this error. Following is what I have tried. Modified the flag in its PE header so that windows loads the ...
3
votes
2answers
3k views

backup from ZynOS but, can not be decompressed with LZS

So I have this rom-0 file from Zyxel router P-660HW-T3 v3 and I would like to decompress it, I tried many tools, one of them you can find here the tool using lzs for decompression which works for some ...
3
votes
1answer
320 views

What is contained in this transmission? (RF pool-temperature sensor base unit receiver)

Note: I've made progress over at the EE stackexchange on pulling bits out of the signal (see https://electronics.stackexchange.com/questions/145714/what-encoding-is-used-in-this-signal), but now i ...
3
votes
1answer
704 views

An issue when unpacking UPX

Since I love to play with the WinAPI or debugging in general, I decided to write a small unpacker for the open source PE executable packer UPX today (Windows version). In order to accomplish this, I ...
3
votes
0answers
1k views

Analysing eCos image

I'm working on unpacking a firmware image. I've already uncompressed the original image, but I'm stuck in the current step. This is the current uncompressed image: https://www.dropbox.com/s/...
3
votes
0answers
632 views

Need help figuring out compression used on a PKDPX file from a Nintendo DS game

So, I've been working on reversing several file formats from the Nintendo DS game Pokemon Mystery Dungeon: Explorers of Sky. So far most formats were pretty easy to reverse, until I stumbled on a ...