Questions tagged [android]

Android is Google's Linux-based operating system for mobile devices. Initially developed by Android, Inc., Android is the world's most widely used smartphone platform.

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6
votes
2answers
1k views

Trace system calls, including stack (and java stack if possible), on android?

I have an android app that reads/writes a data file which seems to be encrypted, and i want to make a tool to read/write that file, so i need to reverse the encryption. The app in question consists ...
9
votes
5answers
3k views

Lifting up binaries of any arch into an intermediate language for static analysis

Background As the title is self-explanatory, I would like to translate binaries of any architecture (e.g. x86, ARM, ARM Thumb) to an intermediate language in order to apply arch-independent static ...
2
votes
1answer
368 views

Removing uncalled smali

Does anyone know of a smali re-compiler that will remove uncalled code without obfuscation? I just want to remove unused classes and methods.
5
votes
1answer
3k views

Reverse engineering Android vendor system apps

I'm trying to reverse engineer certain Samsung system apps in the Galaxy S6 firmware system image, such as KnoxAttestationAgent.apk. I'm a noob when it comes to reverse engineering, and so far my ...
1
vote
0answers
283 views

SSL Unpinning Twitter app [duplicate]

I want to run twitter app behind a proxy so i decompiled the app to read the source code.I have noticed that it is using this code to pin the certificate. https://github.com/moxie0/AndroidPinning/...
1
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0answers
731 views

SSL unpinning Twitter android app [closed]

I want to run twitter app behind a proxy so i decompiled the app to read the source code.I have noticed that it is using this code https://github.com/moxie0/AndroidPinning/tree/master/src/org/...
1
vote
1answer
688 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 ...
14
votes
1answer
10k views

Bypassing certificate pinning in android

I've spent the past 4 months trying to bypass certificate pinning in the Facebook android application so I can understand how it works, but I'm having trouble doing so. I have tried using android ...
1
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0answers
521 views

Android shared Library (.so)

I quite quite new to reverse engineering in General and there are a couple of things I'm unsure of. The app I am reverse engineering uses a couple of android libs in order to sign requests. So far I'...
1
vote
1answer
298 views

Adding/Finding Places for Instructions - Game Library IDA

Is there any way to add instructions to a library in IDA? My predicament is that there is no room in a game library (.so ELF, android) to fit my own code. There is an empty bss segment but IDA doesn't ...
3
votes
2answers
5k views

Working with Android obfuscation

In the case of an PE file or an ELF file, there is quite a lot of material out there on how to approach deobfuscation, dumping from memory, reconstructing symbols etc. For android binaries that does ...
1
vote
1answer
133 views

Discrepancies in function declarations from decompilers?

An Android application I'm analyzing makes calls to a native library to generate a certain value. Here's an example of the native library function declaration from SMALI (Decompiled Java): .method ...
1
vote
1answer
667 views

IDA Strings to Functions (ARM, Protected Functions)

I am working with an ARM (android apk: libgame.so) file that has protected functions (sub_xxxx, etc). The strings are supposed to have cross references with their function, but most of them reference ...
4
votes
1answer
1k views

How Do I get proficient at Reverse engineering?

Please bare with me as I explain this situation. Maybe 10 days ago I took up the challenge of reverse engineering an Android app. Learning from scratch, I installed ADB, Apktool, Android Studio, ...
1
vote
1answer
944 views

Android - Analyzing complex hash algorithm

An APK I'm working on uses some sort of algorithm to generate a hash which is sent along with an HTTP request. I want to figure out how the algorithm works. Decompiling the APK to Java is of no help ...
0
votes
1answer
2k views

Extracting a .DAT file

I want to extract a chunk of text available in an android app. I disassembled the APK and found a .DAT file which seems to carry the text I'm looking for (the file was inside the directory res/raw/). ...
3
votes
3answers
1k views

Android (4.4+) SSL wireless sniffing without certificate changing

I wish to analyze the unencrypted data sent of SSL by an Android APK that uses certificate pinning. This suspicious APK is used to configure a wireless device. I need to determine two things: ...
5
votes
0answers
595 views

Reverse engineering an hydrometer's Bluetooth communication

This is a very specific question. I'm currently working on a project to create an android application capable of reading the values of an hydrometer via Bluetooth. By reading the datasheet, I suspect ...
1
vote
1answer
3k views

Breakpoint to debug Android Native Shared Library

I'm trying to solve FLARE-on 2015 challenge #06 (http://www.flare-on.com/files/2015_FLAREOn_Challenges.zip) using a dynamic analysis approach. It's an Android APK that loads a shared library (...
1
vote
2answers
2k views

Problem with IDA pro 6.8 disassemble galaxy s6 sboot

I have some problem with galaxy s6 boot loader(sboot.bin). From 0x3F000 of that file, I think that there exists the real boot loader. So I tried to disassemble it with ida 6.8 pro (64bit) But It ...
1
vote
1answer
3k views

Opening mono droid .so files in .NET decompiler

What is the format for .so native android files developed in Xamarin Mono droid? From this SO post it appears they are actually .NET IL binaries (not native machine code). However, this other SO post ...
11
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1answer
20k views

Debugging third party android APKs

What are some ways to debug third party android apps (apps you don't have the source code to)? I would like to step through the APK instruction by instruction, and possibly set breakpoints on certain ...
1
vote
2answers
2k views

Android ARM64 kernel disassembly IDA pro64

I extracted Samsung Galaxy S6 kernel image from its stock boot.img. The result is a raw code kernel image. I load into IDA 6.8 (64-bit) using ROM Start: 0xffffffc000205000 size:0x18C020000, load ...
5
votes
2answers
559 views

ARM - Is calling function from external static library possible?

Basically i'm debugging a closed source binary on Android and i want to execute some of my code in between which is large enough not to fit in codecave. So is it possible to compile library with my ...
2
votes
2answers
3k views

Reverse engineering an application's client connection to a host [closed]

Ok guys, I'm a web programmer but I'm completely new to reverse engineering.. So, there's this android app called InstaMessage, I'd like to reverse engineer the client's connection to the server, so ...
1
vote
0answers
61 views

How to modify arm .so? [duplicate]

I want to modify android app writen on c++. It stores its code mostly in .so file. The code is compiled for arm architecture. When I open it in IDA it says that it can only read but modify. But I ...
0
votes
1answer
789 views

Anyone had success with IDA & Windroye/Andydroid/BlueStacks?

Has anyone had luck debugging JNI code inside of an Android Emulator using IDA? I haven't been able to get any of the popular Windows Android emulators to work. Been trying step such as in http://...
2
votes
1answer
301 views

Android malware reversing : constant values

I was trying to reverse engineer an Android Malware sample and I find the following sample when decompiling the jar file I obtained by running dex2jar. if (i >= paramBundle.length()) { ((...
2
votes
1answer
785 views

Android priority values

Reversing some Android malware I see that it sets android:priority to 10000 in the AndroidManifest.xml file. Looking at the Android Documentation I see that it needs a value > -1000 and < 1000. ...
-3
votes
2answers
654 views

What kind of knowledge do I need for Reverse Engineering? [duplicate]

I have some questions about reverse engineering: What do I need for studying RE? Should I know all of programing languages to study RE? (I only intend to reverse Android and Window PC applications ...
5
votes
2answers
8k views

Offset calculation for branch instruction in ARM

As the title says, how to calculate offsets for branch instructions? For example i have following assembly code, 0x60ECE B loc_60EE6 ; ; ; 0x60EE6 LDR.W R2, #0x123 Hex code for location ...
5
votes
1answer
727 views

Replacing small length instruction with larger length instruction

Basically I want to replace MOVS R1, #0x0 with MOV.W R1, #0x123, since later instruction requires 4 bytes it is impossible to simply replace in HEX code. I am using IDA Pro for analyzing native ...
2
votes
0answers
2k views

Remotely debugging Android native ARM library running in Bluestacks

I want to debug a native library loaded by JNI on Android. I have set up the debugging environment to debug native code running on Bluestacks. I got gdbserver installed on rooted Bluestacks, running ...
1
vote
1answer
119 views

Find out how an Android app controls my AV Receiver

I have an Onkyo Audio Receiver (AR), and there is an Android app that I can use to control it, change the volume, the channel etc. As a little project at home, I'm working on an app that can control ...
5
votes
3answers
6k views

Use Android Shared library (.so) files in Linux

I decompiled an APK file,and that program have native codes in a .so file. I want to use that .so file in Linux in order to use inline functions. These codes have functions to connect to a server and ...
1
vote
0answers
607 views

recompiling android app - native method not found

Been trying at this for over a week, and I'm able to modify the needed sections, however I'm running into a major issue while trying to recompile the APK that is making the whole task atrocious. So I'...
4
votes
3answers
15k views

Decompile ARM native binary - IDA Pro detects file as Shared Object

I am trying to decompile a Android ARM native binary using Hex-Rays IDA Pro. IDA detects the possible formats as ELF for ARM (Shared object) Binary file If I choose ELF for ARM (Shared object), ...
11
votes
1answer
4k views

Generating Snapchat Snaptags (“QR” Codes)

For those that haven't seen, Snapchat now has a special type of image based code that allows you to quickly add friends by pointing the camera at the screen, similar to a QR code, called "Snaptags". ...
3
votes
1answer
91 views

Special ink for iPhone (or other mobile) screen for interaction

Last night I was playing Monopoly Zapped with the kids and I because quite intrigued as to how it worked. Basically, you interact with a tablet (or phone) whenever you want to do something... buy ...
1
vote
1answer
248 views

cost, time and tools had Google reverse-engineered Java packages? [closed]

In the context of Oracle vs. Google: This is not a case where Google reverse-engineered Oracle’s Java packages to gain access to unprotected functional elements contained therein. page 48 ...
2
votes
1answer
1k views

Changing .SO files in android cause to damage the apk [closed]

i created an android app(simple cocos2d-x project) that in this project i have a method that takes a string and then render it, in initialize state of my app i pass the "abcde" as parameter to this ...
1
vote
0answers
444 views

Static binary instrumentation tools for android .so libraries?

I'm trying to statically inject code into an android app. The best way would be to use APKStudio and the like, but there are very harsh restrictions on the device and the app itself, so that apk ...
11
votes
8answers
34k views

Repackaging APK file using baksmali and smali

I am a student interested in Android Security. I was trying to modify a APK file using baksmali and smali. However, I am not able to run the repackaged app in my mobile. When I click on the icon it ...
2
votes
1answer
181 views

LastPass Android javascript behaviour

A few weeks ago I made a proof-of-concept app demonstrating how LastPass' method of filling out creds in Chrome was insecure. For those interested the source is at https://github.com/activems/...
0
votes
1answer
672 views

Saving Kik conversations using VirtualBox Android device [closed]

I'm using a virtual Android device on VirtualBox to chat using Kik. Kik doesn't officially support saving conversations, but can I do it using my setup? My thoughts: when I take a snapshot of Andy ...
1
vote
1answer
2k views

R.java to xml file

How does R.java work? In a compiled .apk file, does it contain all constants from the XML files prior to compilation? I've decompiled an app using several Java RE tools, and used apktool to extract ...
2
votes
1answer
318 views

Break on memory access on Android

I want to be able to monitor when a memory address is read from on Android. The binary I am studying stores around 60 bytes to a memory location during initialisation and this buffer is used at some ...
1
vote
0answers
3k views

Debug Android Native Code without source

Id like to debug (to log function calls) native ARM Android Code in a shared library. So far I got no source and tried to disassemble it with IDA, but its hard to track all the calls down to a ...
0
votes
1answer
6k views

Reverse-engineering of an Unity dll

I'm working on a project which requires me to extract, edit, and reproduce part of a proprietary hash algorithm.. which is contained inside a dll. The dll is used by an Unity game, and includes Unity ...
0
votes
2answers
618 views

How to monitor APK files in Android System

Is there a monitoring tool for Android except logcat which works like Process Monitor in Windows ? Thanks